Part Number 50-20

Revision A

M/D TOTCO
INSTRUMENTATION

INSTRUCTION MANUAL
INSTALLATION, OPERATION, MAINTENANCE
AND
ILLUSTRATED PARTS BREAKDOWN

GAS WATCH SYSTEM

P/N 220489

Printed in U.S.A. September 17, 1993

 List of Effective Pages

Manual 50-20 Contains 68 Pages as Follows:

Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993

A through C. . . . . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993
i through vi . . . . . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993
1-1 through 1-2 . . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993
2-1 through 2-10 . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993
3-1 through 3-16 . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993
4-1 through 4-10 . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993
5-1 through 5-14 . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993
A-1 through A-4 . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993
B-1 through B-4 . . . . . . . . . . . . . . . . . . . . . . . .Sept 1993

Visulogger is a registered trademark of M/D TOTCO Instrumentation.

All other product, brand, or trade names used in this publication are the trademarks or
registered trademarks of their respective owners.

Information in this manual is subject to change without notice.

A June 1, 1994
M/D TOTCO
 IMPORTANT SAFETY NOTICE

Proper service and repair is important to the safe, reliable operation of all M/D TOTCO equipment.
The service procedures recommended by M/D TOTCO and described in the technical manuals are
recommended methods of performing service operations. When these service operations require
the use of tools specially designed for the purpose, those special tools should be used as recom-
mended. Warnings against the use of specific service methods that can damage equipment or
render it unsafe are stated in the manuals. These warnings are not exclusive, as M/D TOTCO
could not possibly know, evaluate and advise service people of all conceivable ways in which ser-
vice might be done or of all possible associated hazardous consequences. Accordingly, anyone
who uses service procedures or tools which are not recommended by M/D TOTCO must first sat-
isfy themselves thoroughly that neither personnel safety nor equipment safety will be jeopardized
by the method selected.

June 1, 1994 B
M/D TOTCO
LIMITED PRODUCT WARRANTY

THE FOLLOWING WARRANTY IS EXCLUSIVE AND IN LIEU OF ALL OTHER WARRANTIES,

WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT BY WAY OF LIMITA-
TION, ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PUR-
POSE.

M/D TOTCO warrants to Buyer (“Purchaser”) of new products manufactured or supplied by M/D
TOTCO that such products are, at the time of delivery to the Purchaser, free of material and work-
manship defects, subject to the following exceptions: (a) Any product that has been repaired or
altered in such a way, in M/D TOTCO’s judgment, as to affect the product adversely, including any
repairs, rebuilding, welding or heat treating outside of an M/D TOTCO-authorized facility, (b) Any
product that has, in M/D TOTCO’s judgment, been subject to negligence, accident or improper
storage, (c) Any product that has not been installed, operated and maintained in accordance with
normal practices and within the recommendations of M/D TOTCO, (d) For all items of special
order by Purchaser that are not manufactured by M/D TOTCO, Purchaser should submit warranty
claims directly to the manufacturer thereof.

M/D TOTCO’s obligation under this warranty is limited to repairing or, at its option, replacing any
products which, in its judgement, proved not to be as warranted within the applicable warranty
period. All costs of transportation of products claimed not to be as warranted and of repaired or
replacement products to or from authorized M/D TOTCO service facility shall be borne by Pur-
chaser. M/D TOTCO may, at its sole option, elect to refund the purchase price of the products, and
M/D TOTCO shall have no further obligation under the Sales Agreement.

The cost of labor for installing a repaired or replacement part shall be borne by Purchaser.
Replacement parts provided under the terms of this warranty are warranted for the remainder of
the warranty period of the product upon which installed to the same extent as if such parts were
original components thereof.

The warranty periods for various products are: a) Hydraulics and Mechanical Equipment: one (1)
year from date of installation or fifteen (15) months from date of shipment from M/D TOTCO,
whichever occurs first, b) All Elastomer Diaphragms: six (6) months from date of shipment from
M/D TOTCO, c) Electronic Equipment: six (6) months from date of shipment from M/D TOTCO.

C June 1, 1994
M/D TOTCO
 TABLE OF CONTENTS
Paragraph/Title Page
INTRODUCTION

1-1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

1-2 SCOPE OF MANUAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1-3 INTENDED AUDIENCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1-4 PERSONNEL QUALIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1-5 NOTES, CAUTIONS AND WARNINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1-6 RELATED DOCUMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

DESCRIPTION

2-1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

2-2 FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2-3 MAIN COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2-3-1 Gas Trap Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2-3-2 Glycol Pot. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2-3-3 Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
2-3-3-1 Sample Pump Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
2-3-3-2 Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
2-3-3-3 Flowmeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
2-3-3-4 Infrared Sensor Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
2-3-3-5 Flow Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2-3-3-6 Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2-3-3-7 I.S. Barrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2-3-3-8 "NO FLOW" LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2-3-3-9 "SENSOR OUTPUT" LCD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2-4 THEORY OF OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2-5 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2-6 RELATED EQUIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

INSTALLATION

3-1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3-2 INSTALLATION LOCATION REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3-3 CONTROL UNIT INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3-3-1 Mounting the Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
3-3-2 Grounding the Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
3-3-3 Connecting AC Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
3-3-4 Connecting Signal Output Cable to Control Unit and DAQ . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
3-3-5 Connecting Signal Output Cable to Control Unit and VII . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
3-3-6 Connecting Sample Input and Output Tubing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
3-3-7 Stabilizing the Control Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8
3-3-8 Verifying Infrared Sensor Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8
3-3-9 DAQ "Total Gas" and "No Flow" Sensor Channel Configuration . . . . . . . . . . . . . . . . . . . . . . 3-10
3-3-10 DAQ "Total Gas" Sensor channel Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11
3-3-11 DAQ "No Flow" Sensor Channel Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12
3-3-12 VII Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12

September 17, 1993 i

M/D TOTCO
 GAS WATCH
TABLE OF CONTENTS MANUAL 50-20

Paragraph/Title Page

3-4 GAS TRAP ASSEMBLY INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14

3-5 GLYCOL POT INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
3-6 POWERING UP THE SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15

CHAPTER FOUR - MAINTENANCE

4-1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

4-2 PERIODIC INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4-3 ROUTINE MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4-3-1 Gas Trap Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4-3-2 Glycol Pot. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4-3-3 Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4-4 REPLACEMENT OF CONTROL UNIT PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
4-4-1 Filter Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
4-4-2 Sample Pump Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
4-5 INFRARED SENSOR ASSEMBLY MAINTENANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
4-5-1 Cleaning the Sample Chamber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
4-5-2 Removing the Sensor Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
4-6 TROUBLESHOOTING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

CHAPTER FIVE - ILLUSTRATED PARTS BREAKDOWN

5-1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

5-2 INDEX NUMBERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5-3 PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5-3-1 Figure & Index Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5-3-2 Part Number. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5-3-3 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5-3-4 Units Per Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5-3-5 Use On Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5-4 ABBREVIATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
5-5 RECOMMENDED SPARE PARTS INVENTORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14

APPENDIX A - SHIELDED CABLE GUIDELINES

A-1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

A-1-1 Guidelines for Preventing Cable Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A-1-2 Electrical Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A-1-3 Shielded Cable Splicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A-1-4 Connecting Two Devices with Shielded Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2

APPENDIX B - CONVERSION DATA

B-1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

B-2 TEMPERATURE CONVERSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
B-3 CONVERSION FACTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

ii September 17, 1993

M/D TOTCO
 LIST OF FIGURES

Figure/Title Page

2-1 Gas Trap Assembly: Electric-Motor Type (P/N 235602-001) . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

2-2 Glycol Pot (P/N 219231) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2-3 GAS WATCH Control Unit (P/N 220444) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
2-4 Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
2-5 Control Unit: Main Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
2-6 Infrared Sensor Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7

3-1 Installation Locations: GAS WATCH Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3-2 Control Unit Mounting Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
3-3 Control Unit Base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
3-4 Control Unit AC Power Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
3-5 Electronics Nest: MZ and MS Calibration Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
3-6 Sample Tubing Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14

4-1 Sensor Assembly Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

4-2 Sample Chamber (Cover Removed) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
4-3 Control Unit Wiring Diagram (1 of 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
Control Unit Wiring Diagram (2 of 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10

5-1 GAS WATCH System (P/N 220489) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

5-2 (1 of 2) Gas Trap Assembly - Air Motor (P/N 235602) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
(2 of 2) Gas Trap Assembly - Electric Motor (P/N 235602-001) . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
5-3 Glycol Pot (P/N 219231) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
5-4 (1 of 2) Control Unit (P/N 220444) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
(2 of 2) Control Unit (P/N 220444) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10

LIST OF TABLES

Table/Title Page

2-1 GAS WATCH Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9

3-1 Control Unit "Signal Out" Cable Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

3-2 Configuration Data for DAQ Channels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10
3-3 Calibration Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13

4-1 Troubleshooting Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

5-1 Parts List Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

5-2 Recommended Spare Parts Inventory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14

B-1 Conversion Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2

September 17, 1993 iii

M/D TOTCO
 GAS WATCH
TABLE OF CONTENTS MANUAL 50-20

RELATED TOOLS AND TEST EQUIPMENT

Item Part Number

Digital Voltmeter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 935706-002

Manual Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 940404-001
Voltage Source Simulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233121
Tube Cutter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 999754-001
DAQ Sensor Installation Screwdriver. . . . . . . . . . . . . . . . . . 999701-005

APPROVED EXPENDABLE ITEMS

Item Part Number

Calibration Gas Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . 993300-SERIES

Nylon Tubing, 1/4-inch (6.35 mm) . . . . . . . . . . . . . . . . . . . . 970615-003
Nylon Tubing, 3/8-inch (9.53 mm) . . . . . . . . . . . . . . . . . . . . 970615-006
Tubing, 1/4-inch (6.35 mm) OD . . . . . . . . . . . . . . . . . . . . . . 970615-014
Glycol, Container Assy, 5 gal (18.9 liter) . . . . . . . . . . . . . . . . . . . 218072
Soapless Lather Leak Test Compound (SNOOP) . . . . . . . . Commercial
Safety Solvent, 1, 1, 1, Trichloroethane . . . . . . . . . . . . . . . . 992417-002
Lubricating Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260579-101

iv September 17, 1993

M/D TOTCO
 CHAPTER 1
INTRODUCTION

1-1 INTRODUCTION

This manual contains installation, maintenance, calibration and parts information for GAS WATCH
(P/N 220489), an infrared gas detection system manufactured by M/D TOTCO. Information in this
manual should enable qualified personnel to install, calibrate and maintain a GAS WATCH system.

1-2 SCOPE OF MANUAL

This manual is divided into the following chapters:

❏ Chapter 1 - Introduction to manual
❏ Chapter 2 - Description of system and main components; list of system specifications
❏ Chapter 3 - Installation, configuration and calibration of sensor channel, sensor
calibration
❏ Chapter 4 - Maintenance and troubleshooting
❏ Chapter 5 - Illustrated parts breakdown and recommended spare parts inventory
❏ Appendix A - Guidelines for working with shielded cable
❏ Appendix B - Conversion data

1-3 INTENDED AUDIENCE

This manual is intended for use by field engineering, maintenance, operation and repair personnel.

1-4 PERSONNEL QUALIFICATIONS

The procedures described in this manual should be performed only by persons who have read the
safety notice on Page B of this manual and who are fully qualified and trained to perform the proce-
dures herein.

1-5 NOTES, CAUTIONS AND WARNINGS

Notes, cautions and warnings are presented, when applicable, to aid in understanding and operat-
ing the equipment or to protect personnel and equipment. Examples and explanations follow.

NOTE

Provides additional information about the current topic.

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Chapter 1 GAS WATCH
INTRODUCTION MANUAL 50-20

CAUTION
Provides information to prevent equipment malfunction or damage that
could result in interruption of service.

WARNING
Provides information to prevent equipment malfunction or damage that
could result in serious or fatal injury to personnel or major property loss.

1-6 RELATED DOCUMENTS

M/D TOTCO documents related to the use of this manual are listed below:
• Manual 60-10: Data Acquisition Unit (DAQ) and Sensors
• Manual 60-40: TOTAL System Configuration and Calibration Soft-
ware, Version 3.10
• Manual 28-11: Visulogger II
FIGURE 1
TABLE 1

Page 1-2 September 17, 1993

M/D TOTCO
 CHAPTER 2
DESCRIPTION

2-1 INTRODUCTION

This chapter describes GAS WATCH, its main components and related equipment. Specifications
for GAS WATCH components are listed in Table 2-1.

2-2 FUNCTION

GAS WATCH is a total hydrocarbon sensor system designed for use with M/D TOTCO’s TOTAL
system or Visulogger II (VII). GAS WATCH performs the following functions:
• Collects gas samples released from drilling mud
• Removes moisture and entrained particles from gas samples
• Uses an infrared sensor to analyze gas samples for total hydrocarbon
concentration
• Represents hydrocarbon concentration as a 4-20 ma signal and out-
puts this signal through barriers as either a 4-20 ma signal for a DAQ
or a 1-5 Vdc signal for a VII
• Monitors sample flow rate; lights a red LED and signals the DAQ
when sample flow rate drops below the required minimum rate of 5
scfh (2.4 liters per minute)

2-3 MAIN COMPONENTS

The main components of GAS WATCH are listed below and described in the following paragraphs.
• Gas trap assembly
• Glycol pot
• Control unit

WARNING
Only UL-approved GAS WATCH components are recommended for use
in hazardous locations.
FIGURE 2
TABLE 2

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Chapter 2 GAS WATCH
DESCRIPTION MANUAL 50-20

2-3-1 Gas Trap Assembly

The gas trap assembly (Figure 2-1) separates entrained gases from drilling mud. It is installed on
the shale shaker possum belly, over the flowline inlet and consists of a rotating mud agitator
mounted in a cylindrical housing. As drilling mud flows into the cylindrical housing, agitation
causes entrained gases to be released and collect in the top of the cylinder.

There are two gas trap assembly models. In the basic model (P/N 235602), the agitator is driven
by an air motor. In the other (P/N 235602-001), the agitator is driven by an electric motor that
operates on rig-supplied 120/240 Vac, 60 Hz. The air motor assembly is not recommended for
installations where the motor will be exposed to sub-freezing temperatures.

Figure 2-1. Gas Trap Assembly: Electric-Motor Type (P/N 235602-001)

Page 2-2 September 17, 1993

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GAS WATCH Chapter 2
MANUAL 50-20 DESCRIPTION

2-3-2 Glycol Pot

The glycol pot (P/N 219231) absorbs moisture from the gas sample. It is a 4.5" (114 mm) outer
diameter clear polycarbonate tube with endcaps. It is filled 1/3- to 1/2-full with ethylene glycol and
positioned in the sample line, downstream from the gas trap assembly and close to the control
unit. Gas sample is drawn into the pot and released into ethylene glycol, which absorbs moisture
from the sample. The conditioned sample is then drawn out through the sample tubing and flows
to the control unit.

The glycol pot (Figure 2-2) can hold one gallon (3.78 liters) of liquid and should initially be filled
1/3- to 1/2-full with ethylene glycol. When the initial volume of liquid in the pot has doubled, the
glycol is saturated with water and must be replaced with fresh glycol (Chapter 4 - Maintenance).

Figure 2-2. Glycol Pot (P/N 219231)

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Chapter 2 GAS WATCH
DESCRIPTION MANUAL 50-20

2-3-3 Control Unit

The control unit (P/N 220444) is the main component of GAS WATCH. It transports and filters a
continuous gas sample stream and uses an infrared sensor to analyze the sample for total hydro-
carbon concentration. The sensor outputs a 4-20 ma signal representing hydrocarbon concentra-
tion. This signal passes through a barrier and is output as either a 4-20 ma signal for a DAQ or a
1-5 Vdc signal for a VII.

If sample flow rate drops below the required minimum rate of 5 scfh (2.4 lpm), a red "NO FLOW"
LED on the control panel is illuminated. If a DAQ is present, the control unit signals the DAQ,
which alerts the operator via the alarm horn attached to the Visulogger XC (VXC) Graphics Dis-
play keypad (Figure 3-1).

The control unit is shown in Figure 2-3. All control unit components are mounted inside a stainless
steel, NEMA 4X enclosure. An internal control panel (Figure 2-4) contains the ac power switch,
indicators and switches used during calibration and troubleshooting. All other components are
located behind the control panel (Figure 2-5).

Figure 2-3. GAS WATCH Control Unit (P/N 220444)

Page 2-4 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 2
MANUAL 50-20 DESCRIPTION

The main control unit components are listed below and described in the paragraphs that follow:
• Sample pump assembly
• Filter
• Flowmeter
• Infrared sensor assembly
• Flow switch
• Power supply
• I.S. barrier
• "NO FLOW" LED
• "SENSOR OUTPUT" liquid crystal display (LCD)

Figure 2-4. Control Panel

September 17, 1993 Page 2-5

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Chapter 2 GAS WATCH
DESCRIPTION MANUAL 50-20

Figure 2-5. Control Unit: Main Components

Page 2-6 September 17, 1993

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GAS WATCH Chapter 2
MANUAL 50-20 DESCRIPTION

2-3-3-1 Sample Pump Assembly

The sample pump assembly (P/N 220407) is an electrically driven vacuum pump powered by
95-125 Vac, 47-63 Hz. The pump pulls gas sample from the gas trap assembly, through the glycol
pot and into the control unit. It is mounted to the inside base of the control unit (Figure 2-5).

2-3-3-2 Filter

Gas sample flows from the sample pump through the filter (P/N 972340-002). The filter is an acti-
vated carbon purifier, which adsorbs vapors, aerosols, trace moisture and particles larger than 0.5
micron. It is disposable and should be replaced every 30 days to ensure efficient adsorption and
filtration of impurities (Chapter 4 - Maintenance).

2-3-3-3 Flowmeter

From the filter, sample flows through the 0-20 scfh (9.4 lpm) flowmeter, (P/N 935703-018). The
flowmeter (Figures 2-4, 2-5) is accurate to +/- 4% of full scale. Optimum sample flow rate is 10-15
scfh (4.7 - 7.1 lpm); minimum sample flow rate is 5 scfh (2.4 lpm). These rates are printed on the
control panel, to the right of the flowmeter, as "NOMINAL FLOW" and "LOW FLOW", respectively.

2-3-3-4 Infrared Sensor Assembly

The infrared sensor assembly (P/N 972333-004) uses two infrared light beams of known wave-
lengths to determine sample hydrocarbon concentration and outputs a 4-20 ma signal represent-
ing this concentration. The sensor assembly is powered by +24 Vdc from the internal GAS
WATCH power supply.

The sensor assembly consists of an electronics nest, sample chamber and mounting frame (Fig-
ure 2-6). The electronics nest contains the infrared light source, detector, lenses and process and
signal electronics. The sample chamber contains a mirror and dust filter.

The sensor assembly functions as follows. As gas sample flows through the sample chamber, the
electronics nest emits into the chamber an infrared beam of a wavelength that is not absorbed by
hydrocarbons. The mirror reflects this beam back to the detector in the electronics nest. A second
infrared beam is emitted, comprised of a wavelength that is absorbed only by hydrocarbons.
Depending upon the hydrocarbon concentration of the sample, some of the beam’s energy is
absorbed, and the remainder is reflected back to the detector. The processor compares the signal
produced by the energy returned by the two beams, computes sample hydrocarbon concentration
and outputs a representative 4-20 ma signal.

Figure 2-6. Infrared Sensor Assembly

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Chapter 2 GAS WATCH
DESCRIPTION MANUAL 50-20

2-3-3-5 Flow Switch

The flow switch (P/N 932913-001) monitors the rate of sample flow from the sample chamber to
the control unit SAMPLE OUT exhaust port. If the flow rate is less than the required minimum of 5
scfh (2.4 lpm), the switch activates the control panel "NO FLOW" LED and signals the DAQ, which
alerts the operator via the alarm horn attached to the VXC keypad.

2-3-3-6 Power Supply

The power supply (P/N 943413-074) converts 85-265 Vac input to +24 Vdc for the infrared sensor
assembly, control panel LCD and "NO FLOW" LED (Figure 2-5). It is fused for overload protection.

CAUTION
Although the power supply can accept up to 265 Vac, do not allow the
input power to exceed 125 Vac, as this may damage the sample pump.

2-3-3-7 I.S. Barrier

Outputs from the sensor assembly and flow switch pass through an I.S. barrier (P/N
H10992A-779P) before exiting the control unit (Figure 2-5).

2-3-3-8 "NO FLOW" LED

A red LED on the control panel (Figure 2-4) is powered by +24 Vdc from the power supply and illu-
minates when sample flow rate through the flow switch is less than the required minimum (5 scfh).

2-3-3-9 "SENSOR OUTPUT" LCD

The 4-20 ma sensor output signal can be displayed in the control panel "SENSOR OUTPUT" liq-
uid crystal display (LCD), instead of being output to the DAQ or VII. This is typically done during
installation, calibration and troubleshooting, by placing the control panel "DAQ/DISPLAY" rocker
switch to the "DISPLAY" position (Figure 2-4).

2-4 THEORY OF OPERATION

GAS WATCH functions as follows. Gas is separated from drilling mud and collects in the gas trap
assembly. The sample pump in the control unit draws gas sample from the gas trap, through the
glycol pot and into the control unit where it is filtered, purified and flow-rate regulated. The sample
then passes to the infrared sensor which analyzes it for total hydrocarbon concentration and out-
puts a representative 4-20 ma signal. This signal is output through an I.S. barrier as either a 4-20
ma signal for a DAQ or a 1-5 Vdc signal for a VII.

Analyzed sample passes from the sensor assembly to the control unit SAMPLE OUT exhaust port
through a flow switch. If the rate of sample flow through the switch is less than the minimum
required 5 scfh (2.4 lpm), the switch closes, which activates the control panel "NO FLOW" LED
and sends a signal, through an I.S. barrier, to the DAQ. The DAQ uses this signal to alert the oper-
ator via the alarm horn connected to the VXC keypad.

2-5 SPECIFICATIONS

Specifications for GAS WATCH components are listed in Table 2-1.

Page 2-8 September 17, 1993

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GAS WATCH Chapter 2
MANUAL 50-20 DESCRIPTION

Table 2-1. GAS WATCH Specifications

Parameter Requirements/Limits

Electrical:

Control Unit

Primary Power 95-125 Vac Universal Input

Frequency 47-63 Hz, single phase

Current Requirements 1 amp

Primary Power Fuse 4 amp, slo-blow

DC Power (Internal) One 25-watt fused power supply; outputs +24 Vdc

Gas Trap Assembly w/ Electric

Motor

Primary Power 120/240 Vac, 60 Hz

Gas Trap Assembly w/ Air Motor

Primary Air Power Not to exceed 35 psi (2.46 kg/cm2).

Environmental:

Control Unit

Operating Temperature Range 0oF - 140oF (-18oC - 60oC)

Storage Temperature Range -40oF - 160oF (-40oC - 71oC)

Internal Humidity 0-95% relative humidity, non-condensing

Gas Trap Assembly w/ Air Motor

Operating Temperature Range Above 32oF (0oC)

Mechanical:

Control Unit

Enclosure Stainless steel, NEMA 4X (IP66), with suitable cable glands

Dimensions 14.10" L x 14.10" W x 5.80" H (358.1mm x 358.1mm x

147.3mm)

Distance between Mounting 15.40" (391.2mm)

Holes
Mounting Hole Diameter 0.30" (7.6mm)

Clearance Area Ample clearance in front to allow cover to swing open.

Ample clearance on side and bottom for connecting cables.

Weight 20 lbs (9.9 kg)

(Continued)

September 17, 1993 Page 2-9

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Chapter 2 GAS WATCH
DESCRIPTION MANUAL 50-20

Table 2-1. GAS WATCH Specifications (Continued)

Parameter Requirements/Limits

Glycol Pot:

Dimensions 4.5 " (114.3mm) outer diameter, 24" L (609.6mm)

Capacity One gallon (3.78 liter)

Installation Classification

Control Unit UL-Approved models only: Class I, Division 2, Groups C and

D hazardous locations. IEC 79-11 [Ex ia] IIB T4

Gas Trap Assembly w/ Electric Class I, Division 1, Group C and D hazardous locations
Motor

Infrared Sensor Assembly

Gases Detected Hydrocarbons C1 through C6

Range (C1) 0% to 100% by volume

Repeatability (C1) +/- 3%

Zero Drift (C1) +/- 5% Non-accumulating

Span Drift (C1) +/- 5% Non-accumulating

Output Signal 4-20 ma current into 800 ohm max

Start-up Delay 30 seconds

Voltage Requirements 18-30 Vdc

Current Consumption 350 ma at 24 Vdc

Response Time T90 12 seconds

2-6 RELATED EQUIPMENT

GAS WATCH supplies either a 4-20 ma output signal to a TOTAL DAQ or a 1-5 Vdc signal to a VII.
The DAQ/VII then converts this signal into total hydrocarbon concentration in "units" of gas and
displays the value on connected display devices.

The control unit also supplies a signal to the DAQ when sample flow rate drops below the required
minimum of 5 scfh (2.4 lpm). The DAQ then uses this signal to alert the operator via the alarm
horn connected to the VXC keypad.

Page 2-10 September 17, 1993

M/D TOTCO
 CHAPTER 3
INSTALLATION

3-1 INTRODUCTION

This chapter contains procedures for installing GAS WATCH components, verifying sensor calibra-
tion, configuring and calibrating the DAQ/VII gas sensor channels and powering-up the system.

3-2 INSTALLATION LOCATION REQUIREMENTS

Figure 3-1 shows location requirements for GAS WATCH components and related equipment.

WARNING
Only UL-approved GAS WATCH components are recommended for
installation in hazardous locations.

FIGURE 3
TABLE3

Figure 3-1. Installation Locations: GAS WATCH Components

September 17, 1993 Page 3-1

M/D TOTCO
Chapter 3 GAS WATCH
INSTALLATION MANUAL 50-20

3-3 CONTROL UNIT INSTALLATION

Control unit installation consists of the following:

• Mounting the unit
• Grounding the unit
• Connecting AC power
• Connecting signal output cable between the unit and DAQ or VII
• Connecting sample input and output tubing
• Stabilizing the control unit
• Verifying infrared sensor calibration
• Configuring and calibrating the DAQ "total gas" and "no flow" sensor
channels
• Calibrating the VII "total gas" sensor channel

NOTE

Control unit installation procedures should be performed in the order

listed above and presented in the chapter. Failure to do so may hinder
system performance.

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M/D TOTCO
GAS WATCH Chapter 3
MANUAL 50-20 INSTALLATION

3-3-1 Mounting the Control Unit

Mount the control unit with 1/4-inch bolts through the four mounting holes (Figure 3-2). The unit
may be bolted directly to a rigid structure or bolted to mounting brackets and then clamped
securely to a rigid structure.

Ensure adequate clearance in front of the unit to allow the door to swing fully open. Ensure ade-
quate clearance below and on the side for connecting cables.

Figure 3-2. Control Unit Mounting Dimensions

September 17, 1993 Page 3-3

M/D TOTCO
Chapter 3 GAS WATCH
INSTALLATION MANUAL 50-20

3-3-2 Grounding the Control Unit

Follow the steps below to earth ground and I.S. ground the control unit.

CAUTION
Do not solder earth ground connections. Ensure that earth ground con-
nections are made in non-hazardous areas.

1. Using a solderless terminal lug, fasten a No. 8 solid copper wire (P/N
946624-002) to I.S. grounding lug on control unit base (Figure 3-3).
2. For offshore installation, make a secure connection between free end
of copper wire and rig structure.
For land rig installation, drive a clean, copper-clad grounding rod that
is 8 feet (2.4 m) long and 1/2-inch (12.7 mm) in diameter (P/N
999263-002) into the ground, leaving just enough of the rod exposed
to attach a 1/2-inch ground clamp (P/N 999264-001) and proceed to
Step 3.
3. Use a 1/2-inch ground clamp to make a secure compression connec-
tion between free end of copper wire and grounding rod, keeping
distance between control unit and grounding rod at a minimum.

Figure 3-3. Control Unit Base

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GAS WATCH Chapter 3
MANUAL 50-20 INSTALLATION

3-3-3 Connecting AC Power

Follow the steps below and refer to Figure 3-4 to connect the ac power cable to the control unit.
1. Strip back wire insulation 1/4 inch (6.35 mm) from free end of ac
power cable for each conductor.
2. Open control unit door, and unlock and lift control panel.
3. Route power cable through ac cable gland on side of unit.
4. Observe wire color-coding and connect wires to terminal strip as fol-
lows: ac line (black) to 1, ac neutral (white) to 2.
5. Use mounting bolt located along top of baseplate to secure ac ground
wire (green).

Figure 3-4. Control Unit AC Power Connections

September 17, 1993 Page 3-5

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Chapter 3 GAS WATCH
INSTALLATION MANUAL 50-20

3-3-4 Connecting Signal Output Cable to Control Unit and DAQ

Follow the steps below to connect signal output cable to the control unit and DAQ. Refer to M/D
TOTCO manual 60-10 (Data Acquisition Unit and Sensors) for details on the DAQ field termination
board and analog connectors.
1. Strip back wire insulation 1/4 inch (6.35 mm) from both ends of
shielded, four-conductor sensor cable.
2. Open control unit door and unlock and fully open control panel to
access output terminal block.
3. Route one end of sensor cable through signal output cable gland on
base of unit.
4. Observe output terminal block numbering and refer to Table 3-1 to
connect cable wires to terminal block.
5. Route shielded cable from control unit to DAQ. Before routing cable,
review Appendix A to ensure familiarity with general practices of
working with shielded cable.
6. Refer to Table 3-1 and use DAQ sensor cable installation screwdriver
(P/N 999701-005) to connect cable wires to analog connectors for
DAQ "total gas" and "no flow" sensor channels on DAQ field termina-
tion board.

Table 3-1. Control Unit "Signal Out" Cable Connections

DAQ Field
Control Unit Termination Board VII Junction Box
Output Terminal Analog Connector TOTAL GAS
Block Position Signal Position Channel Pin Position

4 Sensor Signal (+) SIGNAL Not Applicable

1 Sensor Ground GROUND Not Applicable

6 Flow Switch Signal (+) SIGNAL Not Applicable

5 Flow Switch Ground GROUND Not Applicable

3 Sensor Signal (+) Not Applicable B

2 Sensor Ground Not Applicable C

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GAS WATCH Chapter 3
MANUAL 50-20 INSTALLATION

3-3-5 Connecting Signal Output Cable to Control Unit and VII

Follow the steps below to connect signal output cable to the control unit and VII. Refer to M/D
TOTCO manual 28-11 (Visulogger II), for details on the VII.
1. Open control unit door; unlock and fully open control panel to access
output terminal block.
2. Install a 499 ohm, 1% resistor (P/N 911440-404) between pins 5 and
6 on output terminal block. This closes the flow switch circuit and
enables the "NO FLOW" LED to light when activated.
3. Install a 249 ohm, 1% resistor (P/N 911440-377) between pins 2 and
3 on input side of output terminal block (Figure 4-3). This converts
the 4-20 ma signal to a 1-5 Vdc signal for the VII.
4. Strip back wire insulation 1/4 inch (6.35 mm) from both ends of
shielded, four-conductor sensor cable.
5. Route one end of sensor cable through signal output cable gland on
base of control unit.
6. Observe output terminal block numbering and refer to Table 3-1 to
connect cable wires to block.
7. Route shielded cable from control unit to VII junction box. Before
routing cable, review Appendix A to ensure familiarity with general
practices of working with shielded cable.
8. Ensure correct VII junction box connector (typically "Option 6") is pro-
grammed for TOTAL GAS channel. Program channel, if necessary.
9. Refer to Table 3-1 to connect cable wires to TOTAL GAS channel con-
nector on VII junction box.

3-3-6 Connecting Sample Input and Output Tubing

Follow the steps below to connect sample input and output tubing to the control unit.
1. Connect 1/4-inch (6.35 mm) sample tubing (P/N 970615-003) to
"SAMPLE IN" port on control unit base. Tubing should be long
enough to connect to glycol pot, as shown in Figure 3-6.
2. Connect 1/4-inch sample tubing to "SAMPLE OUT" exhaust port on
control unit base (Figure 3-6).
3. Run exhaust tubing from control unit to a Class I, Division 1 hazard-
ous location, preferably near the gas trap assembly.

WARNING
The sample exhaust tubing must be long enough to extend to a Class I,
Division 1 hazardous location. Allowing sample to exhaust into a Class I,
Division 2 hazardous location or into a non-hazardous location may result
in serious or fatal injury to personnel or severe damage to rig.

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Chapter 3 GAS WATCH
INSTALLATION MANUAL 50-20

3-3-7 Stabilizing the Control Unit

The control unit must be allowed to stabilize before infrared sensor calibration can be verified. Fol-
low the steps below to stabilize the unit.
1. Turn control panel power switch (Figure 2-4) to ON position.
2. Lock down control panel; close and lock control unit.
3. Stabilize control unit by allowing it to run for at least one hour.

CAUTION
The control unit must be allowed to stabilize before sensor calibration can
be verified. If the control unit is not allowed to stabilize, sensor calibration
cannot be assured and subsequent sensor output may not be valid.

3-3-8 Verifying Infrared Sensor Calibration

Follow the steps below to check sensor calibration:

1. After stabilizing control unit, open unit and place DAQ/DISPLAY
rocker switch in DISPLAY position.
2. Run air through unit and ensure that "SENSOR OUTPUT" LCD reads
3.85 - 4.15 ma.
3. Ensure calibration gas has not degraded by checking date on gas
tank label; if no date is present, check with rig personnel or supplier to
determine if gas is usable; replace tank if necessary.

CAUTION
Do not use calibration gas that has degraded beyond its approved life
span. Degraded calibration gas invalidates calibration.

4. Connect calibration gas tank (P/N 993300-SERIES) to "SAMPLE IN"

connector. Set tank pressure to 3 - 5 psi (0.21 - 0.35 kg/cm2) and
maintain calibration gas flow rate below 15 scfh (7.1 lpm).
5. Run calibration gas through unit until LCD reading stabilizes.

NOTE

It is not necessary for calibration gas flow rate to be in the nominal range.
A calibration gas flow rate of 5 scfh (7.1 lpm), or greater, is acceptable.

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GAS WATCH Chapter 3
MANUAL 50-20 INSTALLATION

6. Ensure "SENSOR OUTPUT" LCD reading is in acceptable range for

calibration gas used, as specified in Table 3-3.

NOTE

Calibration gas containing at least 2.5% methane is recommended for

calibration.

7. Stop calibration gas flow; disconnect tank from "SAMPLE IN" connector.
If expected readings were observed, proceed to Paragraph 3-3-9. If
expected readings were not observed, proceed to Step 8.
8. Adjust sensor zero point as follows. Run air through unit until LCD
reading stabilizes. Make minor adjustments to electronics nest man-
ual zero screw, labeled "MZ" (Figure 3-5), while observing "SENSOR
OUTPUT" LCD. When reading is 3.85 - 4.15, sensor is calibrated for
zero hydrocarbons.
9. Connect calibration gas tank to "SAMPLE IN" connector. Set tank
pressure to 3 - 5 psi (0.21 - 0.35 kg/cm2) and maintain calibration gas
flow rate below 15 scfh (7.1 lpm).
10. Adjust sensor span point as follows. Run calibration gas through unit
and make minor adjustments to electronics nest manual span screw,
labeled "MS" (Figure 3-5); ensure "SENSOR OUTPUT" LCD is cor-
rect (Step 6 or Table 3-3).
11. Stop calibration gas flow and disconnect tank from "SAMPLE IN" con-
nector.
If expected readings were observed, proceed to Paragraph 3-3-9. If
not, remove sensor from control unit (Chapter 4 - Maintenance) and
send to M/D TOTCO field store for evaluation.

Figure 3-5. Electronics Nest: MZ and MS Calibration Screws

September 17, 1993 Page 3-9

M/D TOTCO
Chapter 3 GAS WATCH
INSTALLATION MANUAL 50-20

3-3-9 DAQ "Total Gas" and "No Flow" Sensor Channel Configuration

To check, edit or create a configuration for DAQ "total gas" and "no flow" sensor channels, you will
need the following:
• A Configuration/Calibration PC connected to the DAQ
• Manual 60-40, TOTAL System Configuration & Calibration Software

NOTE

Configuration & Calibration Software Version 3.30 and subsequent ver-

sions include a GAS WATCH total gas channel (GW-TOTAL GAS) and a
no flow channel (GW-NO FLOW). Software versions prior to Version 3.30
do not include these channels and the channels will have to be added.

Follow the steps below to configure DAQ channels.

1. Refer to Manual 60-40, Chapter 7. Ensure GW-TOTAL GAS channel
and GW-NO FLOW channel are part of SYSTEM/DAQ configuration
and are configured according to Table 3-2. Add channels to configu-
ration, if necessary.
2. Exit SYSTEM/DAQ configuration and send configuration data to DAQ.
3. To display GW-TOTAL GAS channel on a VXC screen, refer to Chap-
ter 9 of Manual 60-40 to configure channel.
To use GW-NO FLOW channel to trigger alarm horn connected to
VXC keypad, configure channel for VXC by setting channel Low limit
to -10 and High limit to 50.
4. When both channels are configured for VXC, exit VXC configuration
and send configuration to DAQ.

CAUTION
If configuration data is not sent to the DAQ, the DAQ will use default con-
figuration data to calculate total hydrocarbon concentration, which may
invalidate calculations.

Table 3-2. Configuration Data for DAQ Channels

Channel Sensor Type Algorithm Sample Rate Filter Value

GW-TOTAL GAS Current Std Positive Fastest 25.0%

GW-NO FLOW Current Std Positive Fastest 100%

Page 3-10 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 3
MANUAL 50-20 INSTALLATION

3-3-10 DAQ "Total Gas" Sensor Channel Calibration

For the DAQ "total gas" sensor channel, calibration defines the relationship between infrared sen-
sor output, in ma, and sample hydrocarbon concentration, as computed by DAQ software. Calibra-
tion is accomplished by identifying the number of sensor counts for two known hydrocarbon
concentrations, namely, zero (air) and the calibration gas.

To perform DAQ sensor channel calibration, you will need:

• A Configuration/Calibration PC connected to the DAQ
• Manual 60-40, TOTAL System Configuration & Calibration Software

Follow the steps below to calibrate the DAQ infrared gas sensor channel.
1. Open control unit and place control panel DAQ/DISPLAY rocker
switch to DISPLAY.
2. Run air through system and ensure "SENSOR OUTPUT" LCD reads
3.85 - 4.15 ma. Place rocker switch to DAQ position.
3. At PC, follow "Analog Calibration" procedure in Chapter 12 of Manual
60-40 to select RAW MIN value for infrared gas sensor channel and
enter "0" for VALUE MIN.
4. Connect calibration gas tank (P/N 993300-SERIES) to free end of
"SAMPLE IN" connector. Set tank pressure to 3-5 psi (0.21 - 0.35 kg/
cm2) and maintain calibration gas flow rate below 15 scfh (7.1 lpm).
5. At control unit, place rocker switch to DISPLAY and ensure "SENSOR
OUTPUT" LCD is in acceptable range for calibration gas used, as
specified in Table 3-3.
6. Place rocker switch to DAQ position.
7. At PC, continue to follow "Analog Calibration" procedure to select
RAW MAX value for infrared gas sensor channel and enter appropri-
ate value for VALUE MAX, in units of 0 - 5000, as follows:
5000 units
X% x = VALUE MAX
100 %

where X% is the percent methane of the calibration gas. For exam-

ple, if calibration gas is 2.5% methane, enter 125 for VALUE MAX.
Table 3-3 lists VALUE MAX units for calibration gas concentrations.
8. At PC, exit Calibration mode.
9. Stop calibration gas flow and disconnect tank from "SAMPLE IN" con-
nector.

September 17, 1993 Page 3-11

M/D TOTCO
Chapter 3 GAS WATCH
INSTALLATION MANUAL 50-20

3-3-11 DAQ "No Flow" Sensor Channel Calibration

To calibrate the DAQ "no flow" sensor channel, you will need the following:
• A Configuration/Calibration PC connected to the DAQ
• Manual 60-40, TOTAL System Configuration & Calibration Software

Follow the steps below to calibrate the "no flow" sensor channel.
1. At the PC, refer to Chapter 12 of Manual 60-40 to enter analog cali-
bration and enter the following values in the corresponding fields on
analog calibration screen:
• 81900 for RAW MIN
• 0 for VALUE MIN
• 296960 for RAW MAX
• 100 for VALUE MAX
2. Exit calibration.

3-3-12 VII Calibration

Follow the steps below and refer to Manual 28-11, if needed, to calibrate the VII total gas sensor
channel.
1. At the VII, identify junction box analog input PCB and connector for
VII total gas channel. Verify channel is displayed on VII screen and
channel’s scaling factor is 5.
2. Refer to Table 3-9 in Manual 28-11 and set analog PCB dip switches
for 0-5 volt input signal.
3. Use voltage source simulator (P/N 233121) to calibrate analog input
PCB for total gas channel, as follows. When simulated input is 1 V,
analog PCB output should be 0 mVdc and 0 units should be displayed
for total gas channel on VII screen. When simulated input is 5 V, ana-
log PCB output should be 1000 mV and 5000 units should be dis-
played for total gas channel on VII screen. Adjust analog PCB, as
needed.
4. At GAS WATCH control unit, ensure a 249 ohm resistor is installed
between pins 2 and 3 on input side of output terminal block (Figure
4-3). Then place DAQ/DISPLAY rocker switch to DISPLAY.
5. Run air through unit and ensure "SENSOR OUTPUT" LCD is
between 3.85 and 4.15 ma.

Page 3-12 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 3
MANUAL 50-20 INSTALLATION

6. Place rocker switch to DAQ position and verify 1.00 V present

between pins B and C of signal output cable. Connect cable to VII
junction box and ensure 0 mVdc present between analog PCB test
points and 0 units displayed for total gas channel on VII screen.
7. Connect calibration gas tank (P/N 993300-SERIES) to "SAMPLE IN"
connector. Set tank pressure to 3-5 psi (0.21 - 0.35 kg/cm2) and
maintain calibration gas flow below 15 scfh (7.1 lpm). Run calibration
gas through control unit.
8. Place rocker switch to DISPLAY and ensure "SENSOR OUTPUT"
LCD reading is in acceptable range for calibration gas used, as speci-
fied in Table 3-3.
9. Place rocker switch to DAQ position. Disconnect signal cable from
junction box and verify correct voltage between pins B and C of signal
output cable (Table 3-3). Then connect cable to junction box and ver-
ify correct voltage present between analog PCB test points (Table
3-3) and correct number of units displayed for total gas channel on VII
screen, according to Table 3-3.
10. Stop calibration gas flow and disconnect tank from "SAMPLE IN" con-
nector.

Table 3-3. Calibration Data

Total Gas
Channel Value
Measured Measured Total Midpoint
Calibration Control Panel Signal Cable Gas Analog PCB (VII Display and
Gas LCD Reading Output Midpoint Output Midpoint VALUE MAX)
(%) (ma) (Vdc) (mVdc) (units)

2.5 4.36 - 4.44 1.12 25 125

10 5.52 - 5.68 1.50 100 500

20 7.12 - 7.28 2.00 200 1000

25 7.92 - 8.08 2.25 250 1250

50 11.85 - 12.15 3.00 500 2500

September 17, 1993 Page 3-13

M/D TOTCO
Chapter 3 GAS WATCH
INSTALLATION MANUAL 50-20

3-4 GAS TRAP ASSEMBLY INSTALLATION

Follow the steps below and refer to Figure 3-6 to install the gas trap assembly.
1. Set gas trap mounting bracket on possum belly frame, directly above
flowline discharge, or as close to it as possible; secure bracket to
frame using C-clamps (P/N 999380-003).
2. Loosen two retaining screws and level gas trap housing so that mud
level is even with weld bead on gas trap housing.
3. Connect 3/8-inch (9.53 mm) nylon tubing (P/N 970615-006) to gas
trap sample tubing. This tubing must be long enough to reach the
glycol pot.

NOTE

If sample line forms a sag, or low point, anywhere between gas trap
assembly and control unit, insert a condensate pot (P/N 230164) into
sample line at sag to remove moisture that may accumulate there.

Figure 3-6. Sample Tubing Routing

Page 3-14 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 3
MANUAL 50-20 INSTALLATION

3-5 GLYCOL POT INSTALLATION

Refer to Figures 2-2 and 3-6 and follow the steps below to install the glycol pot.
1. Position glycol pot in sample line, downstream from gas trap assem-
bly.

NOTE

The glycol pot should be located as close to the gas trap assembly as
possible.

2. Fill pot 1/3 to 1/2-full with ethylene glycol (P/N 218072). Ensure float
is free to move as liquid level changes.
3. Connect tubing from gas trap to 3/8-inch (9.53 mm) elbow on glycol
pot.
4. Connect free end of 1/4-inch (6.35 mm) nylon tubing (P/N
970615-003) from control unit "SAMPLE IN" port to elbow on glycol
pot.

3-6 POWERING UP THE SYSTEM

Follow the steps below to power-up GAS WATCH.

1. Lock down control panel of control unit.
2. Turn gas trap assembly on. If air motor assembly is used, ensure that
motor RPM is 1800 - 2200 RPM and that air pressure does not
exceed 35 psi (2.46 kg/cm2).
3. Turn power switch (Figure 2-4) to ON position and stabilize control
unit by allowing it to run for one hour.
4. Place DAQ/DISPLAY rocker switch on control panel in DISPLAY posi-
tion and observe sensor output in "SENSOR OUTPUT" LCD display
to ensure output signal is between 4 and 20 ma.
5. Observe control panel flowmeter and ensure sample flow rate is
between 10 and 15 scfh (4.7 - 7.1 lpm).
6. Place DAQ/DISPLAY rocker switch in DAQ position. Observe display
devices connected to DAQ or VII and ensure that DAQ/VII is receiving
and properly processing sensor output.

September 17, 1993 Page 3-15

M/D TOTCO
Chapter 3 GAS WATCH
INSTALLATION MANUAL 50-20

Page 3-16 September 17, 1993

M/D TOTCO
 CHAPTER 4
MAINTENANCE

4-1 INTRODUCTION

This chapter contains:

• periodic inspection and routine maintenance procedures
• procedures for replacement of control unit parts
• infrared sensor assembly maintenance
• general troubleshooting procedures
• control unit wiring schematic

4-2 PERIODIC INSPECTION

Perform the following general checks weekly:

• Check cables for cuts, cracks and frayed areas and ensure all con-
nections are secure
• Check all component mounting bolts for looseness; tighten as needed
• Check all sample tubing for nicks, cuts, cracks, pinching. Ensure that
no sags occur in sample tubing between gas trap assembly and con-
trol unit. If present, install a condensate pot (P/N 230164) at point of
sag. Ensure all fittings (inside control unit) are secure.
• Empty condensate pots, if necessary

Check the control panel of the control unit as follows:

• Check flowmeter to ensure optimum flow rate; adjust flow if needed.
• Check "SENSOR OUTPUT" LCD to ensure signal output of 4-20 ma.
• Ensure "NO FLOW" LED is off.

September 17, 1993 Page 4-1

M/D TOTCO
Chapter 4 GAS WATCH
MAINTENANCE MANUAL 50-20

4-3 ROUTINE MAINTENANCE

Routine maintenance of GAS WATCH components is described in the following paragraphs.

4-3-1 Gas Trap Assembly

Maintain the gas trap assembly as follows:

• Clean mud from around ambient air intake on gas trap
• Clean out debris from bottom of trap (inside end cap)

If the gas trap assembly is powered by an air motor, perform the following:
• Clean exhaust filter on gas trap motor with safety solvent (P/N
992417-002)
• Clean and empty accumulated water from rig air filter leading to air
motor
• Use a manual tachometer (P/N 940404-001) to insure air motor RPM
is 1800 - 2200 RPM
• Check oiler for air motor. Add oil (P/N 260579-101) if required and set
drip rate to 2 drops per minute.

4-3-2 Glycol Pot

Check the glycol pot weekly. When the initial volume of glycol in the pot has doubled, the glycol is
saturated with water and must be replaced. Fill the pot 1/3- to 1/2-full with fresh glycol (P/N
218072).

4-3-3 Control Unit

Install a new filter (P/N 972340-002) in the control unit with each new GAS WATCH installation.
Replace the filter every 30 days thereafter. Refer to Paragraph 4-4-1 to replace the filter.

FIGURE 4

Page 4-2 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 4
MANUAL 50-20 MAINTENANCE

4-4 REPLACEMENT OF CONTROL UNIT PARTS

The following parts are approved for removal and replacement. Contact M/D TOTCO Field Engi-
neering before replacing any other parts.
• Fuse (P/N 938201-032) - replace as needed
• Filter (P/N 972340-002) - replace every 30 days (Paragraph 4-4-1)
• Sample pump assembly (P/N 220407) - replace as needed (Paragraph 4-4-2)
• Infrared sensor assembly (P/N 972333-004) - refer to Paragraph 4-5
• Flow switch (P/N 932913-001) - replace as needed
• AC line protector (P/N 935676-006) - replace as needed
• I.S. barrier (P/N H10992A-779P) - replace as needed
• Power supply (P/N 943413-074) - replace as needed

4-4-1 Filter Replacement

The filter is disposable and should be replaced every 30 days to ensure efficient adsorption and fil-
tration of impurities. Follow the steps below to remove and replace the filter.
1. Open control unit and place ac power switch to OFF position.
2. Unlock and lift control panel to expose filter, mounted to panel under-
side (Figure 2-5).
3. Disconnect sample tubing and tubing connectors from filter.
4. Remove filter from holder and replace with new filter.
5. Connect sample tubing and connectors to filter.
6. Close and lock control panel.
7. Place ac power switch to ON position; close and lock control unit.

4-4-2 Sample Pump Replacement

Follow the steps below to replace the sample pump assembly:

1. Open control unit and place ac power switch to OFF position.
2. Fully lift control panel to expose sample pump.
3. Disconnect ac power connections from ac line protector.
4. Disconnect sample tubing from pump assembly.
5. Remove four screws from base of control unit and remove pump
assembly; replace with new pump assembly.
6. Bolt down new pump assembly.
7. Connect sample tubing to pump assembly.
8. Connect ac power connections to ac line protector.
9. Close and lock control panel.
10. Place ac power switch to ON position; close and lock control unit.

September 17, 1993 Page 4-3

M/D TOTCO
Chapter 4 GAS WATCH
MAINTENANCE MANUAL 50-20

4-5 INFRARED SENSOR ASSEMBLY MAINTENANCE

Maintenance of the infrared sensor assembly should be limited to the following:

• Cleaning the sample chamber
• Removing and replacing the sensor assembly

4-5-1 Cleaning the Sample Chamber

The sample chamber should only be cleaned when "SENSOR OUTPUT" LCD readings are con-
sistently low or erratic and all possible explanations for the low readings have been ruled out (see
Table 4-1 - Troubleshooting). Follow the steps below to clean the sample chamber.
1. Open control unit and turn ac power switch to OFF position.
2. Unlock and lift control panel to expose sensor assembly.
3. Disconnect sample tubing from assembly.
4. Remove electrical connector from electronics nest by sliding the end
where the wires connect away from the rest of the connector.
5. Refer to Figure 4-1 and remove four screws from corners of mounting
frame. Do not remove two center screws of mounting frame.

CAUTION
Do not loosen or remove the two center screws on the sensor assembly
mounting frame, as this will invalidate optical alignment of the sensor and
affect the sensor’s ability to be calibrated.

Figure 4-1. Sensor Assembly Removal

Page 4-4 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 4
MANUAL 50-20 MAINTENANCE

6. Remove sensor assembly from control unit.

7. Remove wingnut on end of sample chamber cover; then slide lid and
cover off chamber.
8. Moisten a soft cloth (Kleenex) with water and wipe interior of cover
and cover lid and all internal components of sample chamber, includ-
ing gold mirror (Figure 4-2) and clear window, located opposite mirror
on mounting frame.

CAUTION
Use only water to moisten the cleaning cloth. Other liquids can interfere
with analyses and cause inaccurate sensor output.

9. When chamber has been cleaned, slide cover and lid back onto
chamber and secure with wingnut.
10. Place sensor assembly in control unit and secure mounting frame
with four corner screws (Figure 4-1).
11. Reconnect electrical connector to electronics nest (Figure 4-1).
12. Reconnect sample tubing.
13. Stabilize control unit (Paragraph 3-3-7); then verify sensor calibration
(Paragraph 3-3-8).
14. Close and lock control panel; close and lock control unit.

Figure 4-2. Sample Chamber (Cover Removed)

September 17, 1993 Page 4-5

M/D TOTCO
Chapter 4 GAS WATCH
MAINTENANCE MANUAL 50-20

4-5-2 Removing the Sensor Assembly

The sensor assembly should be removed under the following conditions:

• If the sensor assembly is defective (see Table 4-1).
• If the sensor assembly has to be recalibrated at a field store
• If the sample chamber needs cleaning (Paragraph 4-5-1)
Follow steps 1 through 5 of Paragraph 4-5-1 to remove the sensor assembly from the control unit
and follow steps 10 through 14 to install a new, realigned or cleaned sensor assembly.

4-6 TROUBLESHOOTING

Table 4-1 lists problems that might be observed with GAS WATCH. For each problem, the table
lists probable cause(s), in order of most likely to least likely, and the corrective action(s) for each.
A wiring diagram for the control unit is presented in Figure 4-3.

NOTE

Use a digital voltmeter (P/N 935706-002) to make the measurements

listed in Table 4-1.
TABLE4

Table 4-1. Troubleshooting Guide

Observed Problem Probable Cause Corrective Action

System Inoperative a. No power to system a. Check and correct ac power source

b. Blown fuse b. Replace fuse

c. Faulty ac line protector c. Check for 95-125 Vac from line pro
tector on L1 of LOAD side; replace
line protector if not present.

d. Faulty power supply d. Check for +18 to +32 Vdc on pins 1,

2, and 3 of power supply. If not
present, replace power supply.

"SENSOR OUTPUT" a. Faulty power supply a. Check for +18 to +32 Vdc on pins 1,
LCD inoperative, displays 2 and 3 of power supply. If not
negative values or dis- present, replace power supply.
plays 1_ ._ _

b. Faulty LCD b. Check for 4-20 ma between S+

and S- of sensor assembly. If pre-
sent, replace LCD.

c. Contaminated sample c. If 4-20 ma not present between S+

chamber and S- of sensor assembly, clean
sample chamber (Par. 4-5-1; then
verify sensor calibration (Par. 3-3-8).

d. Uncalibrated sensor d. If sensor calibration cannot be

attained, replace sensor assembly.
Continued

Page 4-6 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 4
MANUAL 50-20 MAINTENANCE

Table 4-1. Troubleshooting Guide (Continued)

Observed Problem Probable Cause Corrective Action

"NO FLOW" LED is on but a. Defective or clogged a. Check sample tubing between flow
flowmeter indicates flow sample tubing or fittings meter and sensor assembly for
rate above 5 scfh cracks, clogs or holes; ensure all
fittings are secure. Repair or replace
tubing and tighten fittings, if needed.
b. Loose screws holding b. Check screws and tighten if neces-
rubber mounting feet sary. Use LOKTITE 242.
to pump housing

c. Faulty flow switch c. Check for 4 ma between pins 5 and

6 on output terminal block (Fig. 2-5)
when sample is flowing. Stop sam-
ple flow and verify 14.5 ma present
between pins 5 and 6. If required
currents are not present, replace
flow switch.

Flow rate is less than 5 a. Defective or clogged a. Check sample tubing between flow
scfh sample tubing or fittings meter and SAMPLE IN port on
control unit for cracks, clogs or
holes; ensure all fittings are secure.
Repair or replace tubing and tighten
fittings, if needed.

b. Clogged filter b. Disconnect tubing from filter inlet.

If flow is restored, replace filter.

c. Faulty sample pump c. If flow is not restored when tubing is

disconnected, check for 95-125 Vac
from ac line protectorl L1 LOAD to
sample pump. If present, replace
sample pump.

d. Faulty ac line protector d. If 95-125 Vac is not present from ac

line protector L1 LOAD, replace line
protector.
At connected display a. Uncalibrated DAQ/VII a. If connected to a DAQ, ensure that
devices, GAS SENSOR "total gas" sensor current between pins 1 and 4 of out
channel values are consis- channel put terminal block is equal to that
tently low when higher val- displayed on LCD. For a VII, check
ues are expected and same for equivalent voltage (Table
corresponding control 3-2). If appropriate current/voltage is
panel "SENSOR OUT- present, recalibrate GAS SENSOR
PUT" LCD readings are channel.
higher.

b. Faulty barrier b. If appropriate current/voltage is not

present between pins 1 and 4,
replace barrier.

Continued

September 17, 1993 Page 4-7

M/D TOTCO
Chapter 4 GAS WATCH
MAINTENANCE MANUAL 50-20

Table 4-1. Troubleshooting Guide (Continued)

Observed Problem Probable Cause Corrective Action

GAS SENSOR channel a. Faulty DAQ/VII sensor a. Recalibrate DAQ/VII "total gas" sen-
values are consistently channel calibration sor channel (Par. 3-3-10/3-3-12).
low when higher values
are expected and when
corresponding "SENSOR
OUTPUT" LCD readings
are low.

b. Contaminated sample b. If output displayed is equal to that

chamber between S+ and S-, check flowme-
ter. If flow rate is in optimum range,
run calibration gas through unit and
observe LCD. If displayed value is
less than expected, clean sample
chamber (Par. 4-5-1); then verify cal-
ibration (Par. 3-3-8).

c. Low sample hydrocar- c. None

bon concentration

"SENSOR OUTPUT" LCD a. Faulty wiring between a. Check wiring and correct, if needed.
readings are erratic/unsta- control unit and DAQ/
ble when rocker switch is VII
set to DISPLAY
b. Faulty power supply b. Check for +18 to +32 Vdc on pins 1,
2 and 3 of power supply. If not
present, replace power supply.

c. Unsteady ac c. Check for steady 95-125 ac input;

correct as needed.

d. Contaminated sample d. Clean sample chamber (Par. 4-5-1);

chamber then verify sensor calibration (Par.
3-3-8). If calibration cannot be veri-
fied, replace sensor assembly.

Gas readings are consis- a. Gas trap assembly a. Clean agitator vent hole.
tently too high. agitator vent hole
clogged

b. Agitator vent hole not b. Mount agitator so that vent hole can
getting fresh air receive fresh air. If not possible,
plumb 3/8" tubing from vent hole to
area with fresh air.

c. Incorrect DAQ/VII sen- c. Recalibrate DAQ/VII "total gas" sen-

sor channel calibration sor channel (Par. 3-3-10/3-3-12)
d. Uncalibrated sensor d. Verify and adjust sensor calibration
(Par. 3-3-8). If sensor cannot be
calibrated, replace sensor assem-
bly.

Page 4-8 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 4
MANUAL 50-20 MAINTENANCE

Figure 4-3. Control Unit Wiring Diagram (1 of 2)

September 17, 1993 Page 4-9

M/D TOTCO
Chapter 4 GAS WATCH
MAINTENANCE MANUAL 50-20

Figure 4-3. Control Unit Wiring Diagram (2 of 2)

Page 4-10 September 17, 1993

M/D TOTCO
 CHAPTER 5
ILLUSTRATED PARTS BREAKDOWN

5-1 INTRODUCTION

This chapter contains an illustrated parts breakdown and recommended spare parts inventory for
GAS WATCH. The illustrated parts breakdown contains illustrations of GAS WATCH components,
with field-replaceable parts/assemblies identified and with an accompanying parts lists describing
the identified parts. The main features of the illustrated parts breakdown are described below.

5-2 INDEX NUMBERS

On the illustrations, each component or stand-alone part is assigned an index number; each
assembly is identified by a circled number. These numbers are used to identify the parts in the
accompanying parts lists.

5-3 PARTS LIST

Each parts list can contain five columns of information, as described in the following paragraphs.

5-3-1 Figure & Index Number

This column lists the figure number and index number of the item described.

5-3-2 Part Number

This column contains the M/D TOTCO part number of the component, assembly or part.

5-3-3 Description

This column contains the name and description of each component, assembly or part. The
description of each item is indented to the right one period ( . ) from the next higher assembly
(NHA) that it is part of.

5-3-4 Units Per Assembly

This column lists the number of units required for one next higher assembly (NHA).

5-3-5 Use On Code

This column is used when there is more than one configuration of a system or assembly. Each
configuration is assigned a Use On Code (A, B, etc.). Then, each configuration’s constituent parts
or assemblies are assigned the same Use On Code as the configuration. For example, the GAS
WATCH system (P/N 220489) containing an air motor-driven gas trap assembly is assigned a Use
On Code of A and the system (P/N 220489-001) with an electric motor-driven gas trap assembly is
assigned a Use On Code of B. Then, in the system parts list on page 5-3, the air-motor gas trap
assembly is assigned a Use On Code of "A", the electric motor-driven gas trap assembly is
assigned a Use On Code of "B" and the control unit and glycol pot are assigned a Use On Code of
"A, B" because they can be used with either configuration.

September 17, 1993 Page 5-1

M/D TOTCO
Chapter 5 GAS WATCH
ILLUSTRATED PARTS BREAKDOWN MANUAL 50-20

5-4 ABBREVIATIONS

Table 5-1 contains standard abbreviations used in parts lists.

FIGURE 5
TABLE 5

Table 5-1. Parts List Abbreviations

Abbreviation Explanation Abbreviation Explanation

AP Attaching Parts NHA Next Higher Assembly

AR As Required NPT National Pipe Thread

ASSY Assembly NP Not Procurable

AWG American Wire Gauge NYL Nylon

BDGH Binding Head OD Outer Diameter

BRS Brass PCB Printed Circuit Board

CSK Countersunk PHHD Phillips Head

CT Count PN Part Number

CTN Carton PNHD Pan Head

EXT External POS Position

FILH Fillister Head PT Point

FLHD Flat Head RD Root Diameter

GA Gauge RDHD Round Head

HD Head REF Reference

HDW Hardware SHLD Shield

HX Hexagonal SLFLKG Self-Locking

ID Inner Diameter SLTD Slotted

INS Inside SST Stainless Steel

INTL Internal ST Self-Tapping

IS Intrinsically Safe STD Standard

LCD Liquid Crystal Display THD Thread

LED Light-Emitting Diode UNC Unified Coarse Thread

LG Length UNF Unified Fine Thread

M/F Male/Female UNS Unified Straight

Thread
MTG Mounting

Page 5-2 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 5
MANUAL 50-20 ILLUSTRATED PARTS BREAKDOWN

Figure 5-1. GAS WATCH System (P/N 220489)

FIGURE UNITS USE

& PART PER ON
INDEX NO. NUMBER DESCRIPTION ASSY CODE

5-1 220489 GAS WATCH SYSTEM, w/ Air Motor-Driven

Gas Trap Assy. . . . . . . . . . . . . . . . . . . . . . . . . . . . .N/A A
5-1 220489-001 GAS WATCH SYSTEM, w/ Electric Motor-Driven
Gas Trap Assy . . . . . . . . . . . . . . . . . . . . . . . . . . . . .N/A B
1 235602 . GAS TRAP ASSY, Air Motor (shown) . . . . . . . . . . . . . .1 A
1 235602-001 . GAS TRAP ASSY, Electric Motor . . . . . . . . . . . . . . . . .1 B
2 219231 . GLYCOL POT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 A, B
3 220444 . CONTROL UNIT, GAS WATCH . . . . . . . . . . . . . . . . . .1 A, B
4 970615-006 TUBING, 3/8-inch (9.53 mm) Nylon . . . . . . . . . . . . . . .N/A A, B
5 970615-003 TUBING, 1/4-inch (6.35 mm) Nylon . . . . . . . . . . . . . . .N/A A, B
* 230164 CONDENSATE POT. . . . . . . . . . . . . . . . . . . . . . . . . . .N/A A, B
* 946624-002 SOLID COPPER WIRE, No. 8 . . . . . . . . . . . . . . . . . . .N/A A, B
* 999263-002 GROUNDING ROD, Copper-clad, 8’ (2.4 m) lg . . . . . .N/A A, B
* 999264-001 GROUND CLAMP, 0.5-inch (12.7 mm). . . . . . . . . . . . .N/A A, B
* Not shown and not included as part of GAS WATCH system

September 17, 1993 Page 5-3

M/D TOTCO
Chapter 5 GAS WATCH
ILLUSTRATED PARTS BREAKDOWN MANUAL 50-20

Figure 5-2. (1 of 2) Gas Trap Assembly - Air Motor (P/N 235602)

Page 5-4 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 5
MANUAL 50-20 ILLUSTRATED PARTS BREAKDOWN

Figure 5-2. (2 of 2) Gas Trap Assembly - Electric Motor (P/N 235602-001)

September 17, 1993 Page 5-5

M/D TOTCO
Chapter 5 GAS WATCH
ILLUSTRATED PARTS BREAKDOWN MANUAL 50-20

FIGURE UNITS USE

& PART PER ON
INDEX NO. NUMBER DESCRIPTION ASSY CODE

5-2 (1 of 2) 235602 GAS TRAP ASSY, Air Motor. . . . . . . . . . . . . . . . . . . . .N/A A

5-2 (2 of 2) 235602-001 GAS TRAP ASSY, Electric Motor . . . . . . . . . . . . . . . . .N/A B
✯ 218409 . AGITATOR ASSY, Gas Trap . . . . . . . . . . . . . . . . . . . . .1 A
✯ 218409-001 . AGITATOR ASSY, Gas Trap . . . . . . . . . . . . . . . . . . . . .1 B
1 235585 . . HOUSING WELDMENT, Gas Trap . . . . . . . . . . . . . . .1 A, B
2 235601 . . AGITATOR SHAFT ASSY . . . . . . . . . . . . . . . . . . . . . .1 A, B
* 999343-020 . . . PIN, Spring, 7/32 x 3 . . . . . . . . . . . . . . . . . . . . . . . .2 A, B
* 999393-222 . . . SCREW, hx, 1/4 - 20 x 1/2 . . . . . . . . . . . . . . . . . . . .4 A, B
* 235600 . . . COUPLING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 A, B
* 235599 . . . SHAFT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 A, B
3 235603 . . AIR MOTOR, Modified . . . . . . . . . . . . . . . . . . . . . . . .1 A
4 971185-007 . . CONNECTOR, m, 1/4 NPT x 1/4 tubing. . . . . . . . . . .1 A
5 999393-246 . . SCREW, hx, 3/8-16 x 1.0 lg . . . . . . . . . . . . . . . . . . . .4 A
6 999321-008 . . WASHER, Splitlock, 3/8 NOM . . . . . . . . . . . . . . . . . .4 A, B
7 969601-014 . . BUSHING, Pipe, 3/4 NPT - 1/2 NPT . . . . . . . . . . . . .1 A, B
8 999356-020 . . BOLT, Hex, 1/2 - 13 unc x 12.0 lg . . . . . . . . . . . . . . . .2 A, B
9 968628-010 . . ELBOW, 90o, 1-1/2 NPT (f). . . . . . . . . . . . . . . . . . . . .1 A, B
10 968170-130 . . NIPPLE, 1-1/2 NPT x 6-in. . . . . . . . . . . . . . . . . . . . . .1 A, B
11 968110-020 . . REDUCER, 1-1/2 NPT (f) x 1.0 NPT (f) . . . . . . . . . . .1 A, B
12 969616-026 . . BUSHING, Reducer, 1.0 NPT (m) x 1/2 NPT (f) . . . . .1 A, B
13 968170-064 . . NIPPLE, 1/2 NPT x 12-in.lg . . . . . . . . . . . . . . . . . . . .2 A, B
14 968116-028 . . COUPLING, Reducer, 1/2 NPT (f) x 1/4 NPT (f) . . . .1 A, B
15 968754-009 . . ELBOW, m, 1/4 NPT x 3/8, tubing connector . . . . . . .1 A, B
16 219079 . . END CAP ASSY, Gas Trap . . . . . . . . . . . . . . . . . . . . .1 A, B
17 970604-019 . . HOSE CLAMP, sst . . . . . . . . . . . . . . . . . . . . . . . . . . .1 A, B
18 219096 . . RETAINER, Cap . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 A, B
19 968106-004 . . COUPLING, 1/2 NPT, sst . . . . . . . . . . . . . . . . . . . . . .1 A, B
20 219368 . . SPLASH PLATE . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 B
21 999393-265 . . SCREW, hx hd, 3/8 - 16 x 1.25 lg, sst . . . . . . . . . . . .4 B
22 979454-006 . . SEAL, Plain, 0.625 shaft x 0.188 thick . . . . . . . . . . . .1 B
23 999279-010 . . NUT, hx, 3/8 - 16, slflkg . . . . . . . . . . . . . . . . . . . . . . .4 A
24 999310-015 . . WASHER, Flat, 3/8, sst . . . . . . . . . . . . . . . . . . . . . . .2 A
25 999393-247 . . SCREW, hx, 3/8 - 16 x 1-1/2 . . . . . . . . . . . . . . . . . . .4 A
26 235586 . BRACKET, Mtg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 A, B
27 235584 . SCREW, Holding . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 A, B
✯ 235607 . AIR FILTER/OILER ASSY . . . . . . . . . . . . . . . . . . . . . .1 A
28 974511-001 . . REGULATOR, Pneumatic, self-relieving. . . . . . . . . . .1 A

Page 5-6 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 5
MANUAL 50-20 ILLUSTRATED PARTS BREAKDOWN

FIGURE UNITS USE

& PART PER ON
INDEX NO. NUMBER DESCRIPTION ASSY CODE
5-2
29 972313-001 . . LUBRICATOR, Air line oiler . . . . . . . . . . . . . . . . . . . .1 A
30 972314-001 . . FILTER, Air, 1/4 NPT . . . . . . . . . . . . . . . . . . . . . . . . .1 A
31 270281-101 . . HANDLE ASSY, Oiler . . . . . . . . . . . . . . . . . . . . . . . . .1 A
32 968754-006 . . ELBOW, m, 1/4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 A
33 968201-002 . . NIPPLE, Pipe, 1/4 NPT . . . . . . . . . . . . . . . . . . . . . . .2 A
34 260579-101 . . OIL, Lubricating . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 A
35 968754-009 . . ELBOW, m, 1/4 NPT, x 3/8 tube . . . . . . . . . . . . . . . . .2 A
36 935696-001 . . GAUGE, 0-100 psi, 1/8 NPT back . . . . . . . . . . . . . . .1 A
37 969602-052 . . BUSHING, brs, 1/4 x 1/8 NPT . . . . . . . . . . . . . . . . . .1 A
* 972314-003 . . FILTER ELEMENT, Replacement filter . . . . . . . . . . .1 A
38 219002 . MOTOR ASSY, Electric, 1/3 HP . . . . . . . . . . . . . . . . . .1 B
* 991201-023 PIPE SEALANT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AR
39 953711-025 MUFFLER. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 A

✯ Assembly is not identified by index number on illustration, but assembly’s component parts are.
* Not shown

September 17, 1993 Page 5-7

M/D TOTCO
Chapter 5 GAS WATCH
ILLUSTRATED PARTS BREAKDOWN MANUAL 50-20

Figure 5-3. Glycol Pot (P/N 219231)

FIGURE UNITS USE

& PART PER ON
INDEX NO. NUMBER DESCRIPTION ASSY CODE

5-3 219231 GLYCOL POT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .N/A

1 969144-009 . PVC CAP, 4.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
2 219227 . MODIFIED PVC CAP, 4.0. . . . . . . . . . . . . . . . . . . . . . .1
3 996871-001 . TUBING, Clear acrylic, 4.5 O.D. . . . . . . . . . . . . . . . . .18 "
4 969145-001 . PLUG, Pipe, PVC, 1.0 NPT . . . . . . . . . . . . . . . . . . . . .1
5 968754-006 . ELBOW, 1/4 tube to 1/4 NPT . . . . . . . . . . . . . . . . . . . .1
6 970673-001 . TUBING, Clear, 1/4 I.D. . . . . . . . . . . . . . . . . . . . . . . . 18"
7 219480 . BUSHING, Reducer, Modified, 1/2 M x 1/4 F NPT . . . .1
8 971160-003 . CONNECTOR, Hose, 1/4 NPT to 1/4 Barb . . . . . . . . .1
9 219230 . FLOAT ASSY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
10 991704 . PVC ADHESIVE SOLVENT . . . . . . . . . . . . . . . . . . . . AR
11 991724-002 . TAPE, Teflon, 1/2" wide . . . . . . . . . . . . . . . . . . . . . . . AR
12 968754-009 . ELBOW, 3/8 tube to 1/4 NPT . . . . . . . . . . . . . . . . . . . .1
13 947619-004 . CABLE TIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
* 218072 GLYCOL, Container Assy (5 gal) . . . . . . . . . . . . . . . . . AR

Page 5-8 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 5
MANUAL 50-20 ILLUSTRATED PARTS BREAKDOWN

Figure 5-4. GAS WATCH Control Unit (1 of 2)

September 17, 1993 Page 5-9

M/D TOTCO
Chapter 5 GAS WATCH
ILLUSTRATED PARTS BREAKDOWN MANUAL 50-20

DETAIL A

DETAIL B

DETAIL C

Figure 5-5. GAS WATCH Control Unit (2 of 2)

Page 5-10 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 5
MANUAL 50-20 ILLUSTRATED PARTS BREAKDOWN

FIGURE UNITS USE

& PART PER ON
INDEX NO. NUMBER DESCRIPTION ASSY CODE

5-4 220444 CONTROL UNIT, GAS WATCH . . . . . . . . . . . . . . . . . .N/A

1 220406 . ENCLOSURE, Modified, GAS WATCH . . . . . . . . . . . .1
2 220407 . VACUUM PUMP, Modified, GAS WATCH . . . . . . . . . . .1
3 220408 . HINGE, Modified, GAS WATCH . . . . . . . . . . . . . . . . . .1
4 220409 . BRACKET, Latch Strike, GAS WATCH . . . . . . . . . . . . .1
5 220410 . FACEPLATE, GAS WATCH . . . . . . . . . . . . . . . . . . . . .1
6 220483 . NUT RING, Vacuum Pump, GAS WATCH . . . . . . . . . .1
* 220412 . CABLE ASSY, DC Power Dist . . . . . . . . . . . . . . . . . . .1
7 220413 . LABEL, Full-Face, GAS WATCH . . . . . . . . . . . . . . . . .1
8 232039 . GROUND STUD, Modified . . . . . . . . . . . . . . . . . . . . . .1
* 219645-102 . CABLE ASSY, I.S. Ground, 10 inch . . . . . . . . . . . . . . .1
* 220465 . LABEL, Identification, GAS WATCH . . . . . . . . . . . . . . .1
11 220473 . MOUNTING BRACKET, Barrier . . . . . . . . . . . . . . . . . .1
12 932312-401 . SWITCH, 2-Pos Selector, ON/OFF. . . . . . . . . . . . . . . .1
13 932312-410 . CONTACT BLOCK, Sealed . . . . . . . . . . . . . . . . . . . . .1
14 932913-001 . FLOWSWITCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
15 220443 . ROCKER SWITCH ASSY, GAS WATCH . . . . . . . . . . .1
16 935676-006 . PROTECTOR, AC Line, 1 amp. . . . . . . . . . . . . . . . . . .1
17 935703-018 . FLOWMETER, 2-20 scfh, Adj, Panel Mount. . . . . . . . .1
18 935748-001 . CURRENT METER, 3-1/2 Digit, LED . . . . . . . . . . . . . .1
19 936508-006 . LED INDICATOR, 24V, panel mount, red . . . . . . . . . . .1
20 938201-032 . FUSE, 4 amp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
21 938700-004 . FUSE HOLDER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
22 943413-074 . POWER SUPPLY, 24V output, UNIV IN . . . . . . . . . . . .1
23 945505-002 . MOUNTING CLIP, Battery . . . . . . . . . . . . . . . . . . . . . .2
24 948500-003 . TERMINAL END CAP w/ Label . . . . . . . . . . . . . . . . . .1
25 948509-004 . LABEL SET, Terminal Block . . . . . . . . . . . . . . . . . . . . .2
26 948510-001 . END PLATE, Terminal Block. . . . . . . . . . . . . . . . . . . . .1
27 948511-001 . JUMPER, 2-Pos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
28 948513-001 . TERMINAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
29 951330-009 . TERMINAL BLOCK SECTION . . . . . . . . . . . . . . . . . . .2
30 951330-010 . END PLATE, Terminal Block. . . . . . . . . . . . . . . . . . . . .1
31 951330-012 . LABEL STRIP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.0"
32 951330-013 . HOLDING PLUG . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
33 955249-9001 . KIT, Mounting feet. . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
* 955249-9002 . KNOB, Quarter turn, T-handle, Front Cover . . . . . . . . .1
35 955701-001 . CABLE GLAND, 1/2 NPT, .125 THRU . . . . . . . . . . . . .1

September 17, 1993 Page 5-11

M/D TOTCO
Chapter 5 GAS WATCH
ILLUSTRATED PARTS BREAKDOWN MANUAL 50-20

FIGURE UNITS USE

& PART PER ON
INDEX NO. NUMBER DESCRIPTION ASSY CODE

5-4 (Cont) 220444 CONTROL UNIT, GAS WATCH . . . . . . . . . . . . . . . . . .N/A

36 960001-002 . LATCH, Lift/Turn. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
37 969101-053 . BULKHEAD UNION, O-Seal, .25 tube . . . . . . . . . . . . .2
38 972333-004 . SENSOR ASSY, GAS WATCH . . . . . . . . . . . . . . . . . . .1
39 972340-002 . FILTER, In-Line Purifier . . . . . . . . . . . . . . . . . . . . . . . .1
40 999216-026 . WASHER, Flat, #6 Nylon . . . . . . . . . . . . . . . . . . . . . . .8
41 999231-030 . HANDLE, Folding . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
42 999268-007 . LOCKWASHER, Split-Ring, #6, Cres . . . . . . . . . . . . . 20
43 999279-007 . NUT, .38, SLFLKG . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
44 999310-006 . WASHER, Flat, #6, Cres . . . . . . . . . . . . . . . . . . . . . . 22
45 999310-015 . WASHER, Flat, .38, Cres . . . . . . . . . . . . . . . . . . . . . . .6
46 999321-008 . LOCKWASHER, Split-Ring, .38 . . . . . . . . . . . . . . . . . .3
47 999397-503 . NUT, .38, Bronze . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
48 999411-016 . WASHER, Shoulder, .38, Fiber. . . . . . . . . . . . . . . . . . .6
49 999397-260 . NUT, .38-24, Cres. . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
50 999449-068 . SCREW, 6-32 x .38, PNH, SLTD, Cres. . . . . . . . . . . . 20
51 A11424A-10 . RAIL, Terminal MTG . . . . . . . . . . . . . . . . . . . . . . . . . . .1
52 B1833-1 . WASHER, Sealing, 1/2 NPT. . . . . . . . . . . . . . . . . . . . .2
* H10711A-02 . FERRULE, 20 AWG . . . . . . . . . . . . . . . . . . . . . . . . . . .6
53 H10992A-779P . BARRIER, I.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
54 J857-2 . LOCKNUT, Conduit, 1/2 NPT, Cres . . . . . . . . . . . . . . .2
55 999376-001 . STANDOFF, 6-32 x .25 M/F, Cres, .25 HX 3001.57 . . .4
56 999449-166 . SCREW, 10-32 x .38, PNH, SLTD, Cres. . . . . . . . . . . .1
57 999269-004 . WASHER, Flat, #10, Cres . . . . . . . . . . . . . . . . . . . . . .2
58 955706-005 . CONNECTOR, Cord. . . . . . . . . . . . . . . . . . . . . . . . . . .1
59 G10092A-02 . WASHER, Sealing, #6, Nylon. . . . . . . . . . . . . . . . . . . 10
60 999449-072 . SCREW, 6-32 x .50, PNH, SLTD, Cres. . . . . . . . . . . . 12
61 999449-064 . SCREW, 6-32 x .25, PNH, SLTD, Cres. . . . . . . . . . . . .8
* 946613-052 . WIRE, 22 AWG, Wht/Blu . . . . . . . . . . . . . . . . . . . . . .6.0"
* 946613-043 . WIRE, 22 AWG, Blu . . . . . . . . . . . . . . . . . . . . . . . . . .6.0"
* 219531-001 . CABLE ASSY, AC In. . . . . . . . . . . . . . . . . . . . . . . . . . .1
* 220494-001 . LABEL, "AC IN" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
62 220494-003 . LABEL, "SAMPLE AIR IN/OUT" . . . . . . . . . . . . . . . . . .1
63 220494-002 . LABEL, "I.S. GND" . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
64 955264-001 . SAMPLE CHAMBER . . . . . . . . . . . . . . . . . . . . . . . . . .1
65 948500-001 . LOCK, Terminal Block . . . . . . . . . . . . . . . . . . . . . . . . .1
* 218608 . DATA CARD, Product Maintenance/Repair . . . . . . . . .1

Page 5-12 September 17, 1993

M/D TOTCO
GAS WATCH Chapter 5
MANUAL 50-20 ILLUSTRATED PARTS BREAKDOWN

FIGURE UNITS USE

& PART PER ON
INDEX NO. NUMBER DESCRIPTION ASSY CODE

5-4 (Cont) 220444 CONTROL UNIT, GAS WATCH . . . . . . . . . . . . . . . . . .N/A

* 999764-001 . ENVELOPE, Self-Adhesive, Data Card . . . . . . . . . . . .1
* 220495 . LABEL, General Information. . . . . . . . . . . . . . . . . . . . .1
66 970633-001 . INSERT, 1/4T, BRS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2
67 220488 . INSULATOR, Nylon, Barrier Bracket. . . . . . . . . . . . . . .1
* J10535A-002 . RIVETS, Pop, .128 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
* 968638-001 . FITTING, Elbow, Swivel, 169PL-4 . . . . . . . . . . . . . . . .6
* 971154-003 . FITTING, 66PL-4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . .2
68 971185-006 . FITTING, 68PL-4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . .1
* 968754-013 . FITTING, Elbow, 165PL-4 . . . . . . . . . . . . . . . . . . . . . .2
* 970615-014 . TUBING, Internal Control Unit, .25 OD. . . . . . . . . . . . 60"
* 950801-009 . RING, Terminal, #8 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
* 946613-073 . WIRE, 18 AWG, Blk . . . . . . . . . . . . . . . . . . . . . . . . . . 26"
* 950835-008 . TERMINAL, .188 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
* 219645-101 . CABLE ASSY, Ground, 5" . . . . . . . . . . . . . . . . . . . . . .1
* 947619-001 . TIEWRAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AR

* Not shown

September 17, 1993 Page 5-13

M/D TOTCO
Chapter 5 GAS WATCH
ILLUSTRATED PARTS BREAKDOWN MANUAL 50-20

5-5 RECOMMENDED SPARE PARTS INVENTORY

Table 5-2 lists spare parts which should be kept in stock to minimize downtime when replacement
of parts is necessary.

Table 5-2. Recommended Spare Parts Inventory

Figure &
Index No. Part Number Description Quantity

* 993300-SERIES Calibration Gas, minimum 2.5% methane 3

* 218072 Glycol, Container Assy (5 gal) 5

5-1-2 219231 Glycol Pot Assy 1

5-1-4 970615-006 Tubing, Nylon, 3/8-inch (9.53 mm) 100 ft (30 m)

5-1-5 970615-003 Tubing, Nylon, 1/4-inch (6.35 mm) 100 ft (30 m)

5-2-2 235601 Agitator Shaft Assy 1

5-2-* 972314-003 Filter Element, Replacement Filter 2

5-2-34 260579-101 Oil, Lubricating 1

5-2-39 953711-025 Muffler 2

5-4-2 220407 Vacuum Pump, Modified, GAS WATCH 1

5-4-14 932913-001 Flowswitch 1

5-4-17 935703-018 Flowmeter, 2-20 scfh, Adj, Panel Meter 1

5-4-20 938201-032 Fuse, 4 amp 1

5-4-39 972340-002 Filter, In-line purifier 1

5-4-77 970615-014 Tubing, Internal Control Unit, 1/4 OD 60 in (150 cm)

* Not shown

Page 5-14 September 17, 1993

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 APPENDIX A
SHIELDED CABLE GUIDELINES

A-1 INTRODUCTION

This appendix provides guidelines for connecting sensor signal cables.

A-1-1 Guidelines for Preventing Cable Damage

Observe the following practices when routing sensor signal cables.

• Route cables so that they are out of walkways and are not exposed to
sharp corners that could wear through insulation.
• Plan signal cable runs to avoid wet areas and close proximity to
power cables.
• Use nylon (land rig) or stainless steel (offshore rig) tie wraps to dress,
secure and support cables.
• Protect splices from moisture and excessive strain.

A-1-2 Electrical Interface

Use shielded cable whenever signal cables must be run in cable trays or otherwise located next to
electrical power cables. This prevents induced noise from causing erratic sensor channel values.

A-1-3 Shielded Cable Splicing

Sensor cables must typically be spliced in the field. Figure A-1 shows the recommended method
of using butt splices to join two pieces of shielded cable or a length of shielded cable and a
shielded cable pigtail assembly.

WARNING
Plan each rig-up so that splices are not located in hazardous areas.

Follow the guidelines below when splicing shielded cable:

• When joining two cables, cut individual conductors (Figure A-1).
• Stagger butt splices along length of cable splice.
• Observe color code when cutting and splicing conductors.
• Use a crimping tool and apply enough pressure on each butt splice
connector to ensure a good compression connection between con-
ductor and connector.
• Always seal and protect each splice with a strip of mastic tape that
extends up the cable about one inch past both sides of splice and
wrap mastic tape securely with black electrical tape.

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Appendix A MUDWATCH
SHIELDED CABLE GUIDELINES MANUAL 60-22

A-1-4 Connecting Two Devices with Shielded Cable

Follow the guidelines below when connecting two devices with shielded cable.
• Connect shield to ground at only one end of cable. When connecting
a DAQ and sensor, connect shield to ground only at DAQ end.

CAUTION
If the shield is connected to ground at both ends of the cable, the shield
will attract electrical interference, rather than shield against it.

• When using butt splice connectors to fabricate a length of shielded

cable, splice cable to shield only in pigtail connected to DAQ. At other
end of cable, cut off shield even with cable insulation; do not connect
shield to any other shield or device.
FIGURE 1

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MUDWATCH Appendix A
MANUAL 60-22 SHIELDED CABLE GUIDELINES

Figure 1-1. Recommended Method of Splicing Shielded Cable

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Appendix A MUDWATCH
SHIELDED CABLE GUIDELINES MANUAL 60-22

Page A-4 October 18, 1993

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 APPENDIX B
CONVERSION DATA

B-1 INTRODUCTION

This chapter contains the following conversion information:

• Methods for converting temperature from degrees Fahrenheit (oF) to
degrees Centigrade (oC) and vice versa
• Conversion factors for commonly used units

B-2 TEMPERATURE CONVERSIONS

To convert from degrees Fahrenheit (oF) to degrees Centigrade (oC), subtract 32 from the degrees
Fahrenheit, then multiply by 0.556, as shown below:

oC = [ oF - 32 ] x 0.556

To convert from degrees Centigrade (oC) to degrees Fahrenheit (oF), multiply the degrees Centi-
grade by 1.7985, then add 32, as shown below:

o
F = [ oC x 1.8 ] + 32

B-3 CONVERSION FACTORS

Conversion factors for commonly used units are presented in Table B-1.

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APPENDIX B GAS WATCH
CONVERSION DATA MANUAL 50-20

Table B-1. Conversion Factors

MULTIPLY BY TO OBTAIN
atmospheres (atm) 101.325 kiloPascal (kPa) absolute
atmospheres (atm) 14.7059 pounds per square inch (psi)
barrels (bbl) of petroleum 5.615 cubic feet (ft3)
barrels (bbl) of petroleum 0.159 cubic meters (m3)
barrels (bbl) of petroleum 42 gallons, U.S. liquid
barrels of petroleum per inch (bbl/in) 0.626 cubic meters per centimeter (m3/cm)
bars 14.5138 pounds per square inch (psi)
centimeters 0.394 inches (in)
centimeters per second (cm/sec) 0.0328 feet per second (ft/sec)
cubic feet (ft3) 7.4805 gallons, U.S. liquid
cubic feet (ft3) 28.32 liters
3
cubic feet (ft ) 0.178 barrels (bbl) of petroleum
cubic meters (m3) 6.289 barrels (bbl) of petroleum
cubic meters (m3) 264.2 gallons, U.S. liquid
3
cubic meters per centimeter (m /cm) 1.597 barrels of petroleum per inch (bbl/in)
decaNewtons (daN) 2.248 pounds
feet (ft) 0.3048 meter (m)
feet per hour (ft/hr) 0.3048 meters per hour (m/hr)
feet per minute (ft/min) 0.01829 kilometers per hour (km/hr)
feet per minute (ft/min) 0.3048 meters per minute (m/min)
feet per second (ft/sec) 30.48 centimeters per second (cm/sec)
feet per second (ft/sec) 18.29 meters per minute (m/min)
foot-pound 1.4882 kilogram-meter (kg-m)
foot-pound 1.3558 Newton-meter
gallons, U.S. liquid 0.0238 barrels (bbl) of petroleum
gallons, U.S. liquid 0.13368 cubic feet (ft3)
gallons, U.S. liquid 0.003785 cubic meters (m3)
gallons, U.S. liquid 3.7854 liter
grams per cubic centimeter (g/cm3) 8.345 pounds per U.S. liquid gallon (lb/gal)
inch (in) 2.54 centimeter (cm)
inches Hg (Mercury) 0.4912 pounds per square inch (psi)
inches H20 (Water) 0.0361 pounds per square inch (psi)
kilograms (kg) 2.2046 pounds
kilogram-meters (kg-m) 0.67196 foot-pound
kilograms per cubic meter (kg/m3) 0.00835 pounds per U.S. liquid gallon (lb/gal)
kilograms per meter (kg/m) 0.672 pounds per foot
kilograms per square centimeter (kg/cm3) 14.2227 pounds per square inch (psi)

(Continued)

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GAS WATCH APPENDIX B
MANUAL 50-20 CONVERSION DATA

MULTIPLY BY TO OBTAIN
kilometers (km) 0.6215 miles
kilometers per hour (km/hr) 54.6747 feet per minute (ft/min)
kiloPascals (kPa) 0.0099 atmospheres (atm)
kiloPascals (kPa) absolute 0.145 pounds per square inch (psi)
liters (l) 0.0353 cubic feet (ft3)
liters (l) 0.2642 gallon, U.S. liquid
liters per minute (lpm) 2.1186 standard cubic feet per hour (scfh)
meters 3.281 feet (ft)
meters per hour (m/hr) 3.2808 feet per hour (ft/hr)
meters per minute (m/min) 3.2808 feet per minute (ft/min)
meters per minute 0.0547 feet per second (ft/sec)
miles 1.609 kilometers (km)
Newtons 0.2284 pounds
Newton-meters 0.7376 foot-pounds
pounds (lb) 0.4448 decaNewtons (daN)
pounds (lb) 0.4536 kilograms (kg)
pounds (lb) 0.000454 metric tons
pounds (lb) 4.448 Newtons (N)
pounds (lb) 0.0005 U.S. tons
pounds per foot (lb/ft) 1.488 kilograms per meter (kg/m)
pounds per gallon (lb/gal) 0.119826 grams per cubic centimeter (g/cm3)
pounds per gallon (lb/gal) 119.826 kilograms per cubic meter (kg/m 3)
pounds per square inch (psi) 0.0680 atmospheres (atm)
pounds per square inch (psi) 0.0689 bars
pounds per square inch (psi) 2.0358 inches of Hg (Mercury)
pounds per square inch (psi) 27.6778 inches of H20 (Water)
pounds per square inch (psi) 0.0703 kilograms per square centimeter (kg/cm2)
pounds per square inch (psi) 6.895 kiloPascals (kPa)
square centimeters (cm2) 0.155 square inch (in2)
square feet (ft2) 0.0929 square meter (m2)
square inch (in2) 6.4516 square centimeter (cm2)
square meter (m2) 10.764 square feet (ft2)
standard cubic feet per hour (scfh) 0.472 liters per minute (lpm)
tons, metric 2205 pounds
tons, metric 1.1025 U.S. tons
tons, U.S. 0.907 metric tons
tons, U.S. 2000 pounds
metric ton-kilometers (tonne-km) 0.6853 U.S.ton-miles
U.S.ton-miles 1.4593 metric ton-kilometers (tonne-km)

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APPENDIX B GAS WATCH
CONVERSION DATA MANUAL 50-20

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