YOUR PRESSURE AND

TEMPERATURE SWITCH SOURCE

B-SERIES SWITCHES
PRESSURE
DIFFERENTIAL PRESSURE
TEMPERATURE

A Halliburton Company

BULLETIN SW-10
 The Dresser Control Instrument ety of precision switch elements are
B-SERIES Operation supplies highly reliable available to meet every application
PRODUCT Ashcroft® switches and controls for
industrial and process applications. We
requirement, including hermetically
sealed contacts for added reliability and
INFORMATlON begin with rock-solid designs, matching safety. The actuators we use have been
the most appropriate technology with proven in more than 20 years of service
the safety and reliability requirements of in the world’s plants and mills. Special
the applications. The materials of con- designs are available for fire safety,
struction are specified to Dresser’s NACE, limit control and other more
exacting standards, and product is built stringent requirements. Simplicity and
to last in the toughest applications. Our ease of use are stressed to improve
modern, responsive manufacturing facil- reliability of the installation.
ity in Milford, Connecticut is supported
B-Series switches have proven reliable
by an extensive network of stocking dis-
in such harsh environments as:
tributors and factory sales offices locat-
ed in virtually every part of the world. • Offshore oil rigs
Special application assistance is always • Chemical and petrochemical plants
just a telephone call away. • Pulp and paper mills
The Ashcroft B-Series switch line is • Steel mills
designed to satisfy most switch require- • Power plants
ments. Materials of construction have • Water and sewage-treatment plants
been selected for long life. A wide vari- • Other corrosive environments

Type 400 Enclosure

UL and CSA listed instrument Epoxy-coated aluminum enclosure for

quality snap-action switch for reliable corrosion resistance. Meets NEMA 3,
operation. Ratings up to 10A dc or 4, 4X, 13 and IP66 requirements.
20A ac. Hermetically sealed switch
also available.

Accessible adjustment for convenient

switch setting, includes vibration-
resistant feature.

3
⁄4 NPT electrical connection for
easy wiring.
Neoprene gasket for sealing
enclosure.

High proof pressure.

Standard pressure connection materials:

Pressure psi ranges – 316 SS Deadband limits for each switch.
Differential psid ranges – Nickel-plated brass
Pressure and differential I.W. ranges –
Epoxy-coated carbon steel

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Applications include: pumps, compres- RECOMMENDED PRACTICE:
sors, washers, filters, degreasers, All controls should be selected consid-
evaporators, recovery systems, food
processing, ground support equip- ering the media and ambient operating
ment, reverse osmosis systems, heat conditions. Improper application can
exchangers, hydraulic systems, lubrica- be detrimental to the switch, cause
tion systems, marine equipment, textile
machinery, heating and air conditioning failure and possibly personal injury
equipment. or property damage.
Hermetically Sealed Switch The information in this catalog is offered
We recommend hermetically sealed
switch elements for improved reliability. as a guide to assist in making the
The hermetically sealed switch provides proper selection of Ashcroft controls.
uncompromising contact protection in Features:
harsh or corrosive environments. The • UL-recognized component, guide Additional information is available
Ashcroft 400 Series is also approved WSQ2, File E85076 from Dresser Control Instrument
for installation in Division II hazardous
• All-stainless steel welded construction Operations Sales. Offices are listed
areas when supplied with hermetically
sealed contacts. on the back cover.

Type 700 Enclosure

Terminal block wiring standard
UL and CSA listed instrument Deadband limits for each switch.
on dual switches. Optional
quality snap-action switch for
(XK3) on single switches.
reliable operation. Ratings up to High proof pressure.
10A dc or 20A ac. Hermetically
sealed switch also available.
Dual (2 SPDT) shown.

Epoxy-coated aluminum enclo-

sure and cover for corrosion
resistance. Class 1, Division 1 &
2, Groups B, C, D, Class 2, Divi-
sion 1 & 2, Groups E, F, G,
NEMA 7 & 9 and IP66.

Buna-N 0-ring for sealing

enclosure.

Two 3⁄4 NPT electrical conduit

connections.

Standard 316 SS pressure

connection. Optional 1⁄2 NPT
shown.

Accessible adlustment is stainless

steel for corrosion resistance,
includes vibration-resistant feature.

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 PRESSURE AND DIFFERENTlAL PRESSURE SWITCHES

B-Series pressure, differential pressure 316 SS or Monel. Differential pressure All standard models feature ±1 percent
and vacuum switches use two different models use a unique, dual diaphragm- of range setpoint repeatability and a
actuators depending on setpoint require- sealed piston design that features very minimum of 400 percent of range proof
ments. For setpoints between 2 and high static operating pressures and pressures.
3000 psi, the simple, rugged diaphragm- small size.
sealed piston actuator is used. This These standard designs perform well in
design features high reliability and For setpoints between 4.5 and 150 applications where shock and vibration
choice of actuator seal materials for inches of H2O, a large diaphragm is could be a problem and may be used in
virtually every application. An optional used for increased sensitivity in both conjunction with Ashcroft diaphragm
welded design is also available for pressure and differential pressure seals in extreme services such as slur-
setpoints up to 1000 psi for maximum designs with good choice of materials ries or abrasive process fluids.
reliability. This design is available in of construction.

PRESSURE/VACUUM SWITCHES
Overpressure Ratings Approximate Deadband(2) Switch Element
Nominal Range(1) Proof psi Burst psi 20, 26, 27 21, 24, 31 50 22 32
Vacuum
–30˝ Hg –760mm Hg -100 kPa 250 400 0.3-0.7 1.5-3.0 0.5-2.2 0.4-1.5 2.1-4.2
Compound
–15˝ H2O/ –375mm H2O/ –3.7 kPa/ 20 35 0.15-75/ 1.5-2.5/ 0.45-2.0/ 0.5-1.2/ 2.1-3.5/
15˝ H2O 375mm H2O 3.7 kPa 0.15-75 1.5-2.5 0.45-2.0 0.5-1.2 2.1-3.5
–30˝ H2O/ –760mm H2O/ –7.5 kPa/ 20 35 0.30-60/ 1.5-2.5/ 0.45-2.0/ 0.5-1.5/ 2.1-3.5/
30˝ H2O 760mm H2O 7.5 kPa 0.30-60 1.5-2.5 0.45-2.0 0.5-1.5 2.1-3.5
–30˝ Hg/ –760mm Hg/ –100 kPa/ 0.5-1.0/ 2.0-3.0/ 0.75-2.5/ 0.7-1.8/ 2.8-4.2/
15 psi 1.0 kg/cm2 100 kPa 250 400 0.3-0.7 0.5-1.5 0 .5-1.0 0.7-1.4 0.7-2.1
–30˝ Hg/ –760mm Hg/ –100 kPa/ 1.0-1.5/ 3.0-6.0/ 1.2-4.5/ 1.4-2.4 4.2-8.4/
30 psi 2.0 kg/cm2 200 kPa 250 400 0.3-0.8 1.0-2.0 0.7-1.5 0.4-1.3 1.4-2.8
–30˝ Hg/ –760mm Hg/ –100 kPa/ 2.0-3.0/ 5.0-9.0/ 2.5-7.0/ 2.8-4.5 7.0-12.0/
60 psi 4.0 kg/cm2 400 kPa 250 400 0.7-1.5 3.0-5.0 1.1-4.0 1.0-2.3 4.2-7.0
Pressure
10˝ H2O 250mm H2O 2.5 kPa 20 35 0.2-0.5 1.0-2.0 0.35-1.5 0.4-1.0 1.4-2.8
30˝ H2O 750mm H2O 7.5 kPa 20 35 0.3-0.6 1.5-2.5 0.45-2.0 0.5-2.0 2.1-3.5
60˝ H2O 1500mm H2O 15 kPa 20 35 0.5-1.3 1.5-3.5 0.9-2.5 0.7-3.0 2.1-5.0
100˝ H2O 2500mm H2O 25 kPa 20 35 0.6-1.6 2.5-5.5 1.1-4.0 1.0-4.0 3.5-7.7
150˝ H2O 3750mm H2O 37 kPa 20 35 1.0-2.5 4.5-8.5 1.7-6.5 2.0-6.0 6.0-12.0
15 psi 1.0 kg/cm2 100 kPa 500 1500 0.1-0.35 0.5-1.5 0.2-1.0 0.4-1.0 0.7-2.1
30 psi 2.0 kg/cm2 200 kPa 500 1500 0.1-0.50 0.5-1.5 0.3-1.0 0.4-1.0 0.7-2.1
60 psi 4.0 kg/cm2 400 kPa 500 1500 0.3-1.0 1.0-3.5 0.7-2.5 0.6-2.0 1.4-5.0
100 psi 7.0 kg/cm2 700 kPa 1000 3000 0.5-1.7 1.5-5.0 1.1-3.5 1.0-4.5 2.1-7.0
200 psi 14 kg/cm2 1400 kPa 1000 3000 1-3 5-13 2-9 3.0-7.5 7.0-18.2
400 psi 28 kg/cm2 2800 kPa 2400 3000 4-7.5 5-24 5.5-15 4.0-11.0 7.0-33.6
600 psi 42 kg/cm2 4200 kPa 2400 3000 4-11 9-30 7-20 5.0-23.0 12.6-42
1000 psi 70 kg/cm2 7000 kPa 12000 18000 7-30 30-110 18-70 15-80 42-154
3000 psi 210 kg/cm2 2100 kPa 12000 18000 15-60 80-235 37-160 30.0-230 112-329

PRESSURE/VACUUM SWITCHES
Pressure Ratings Approximate Deadband(2) Switch Element
Static Work-
Nominal Range(1) ing Pressure Proof psi 20, 26, 27 21, 24, 31 50 22 32
30˝ H2O 750mm H2O 7.5 kPa 5.4 21.6 0.3-0.6 1.5-2.5 0.45-2.0 0.5-2.0 2.1-3.5
60˝ H2O 1500mm H2O 15 kPa 5.4 21.6 0.5-1.3 1.5-3.5 0.9-2.5 0.7-3.0 2.1-5.0
100˝ H2O 2500mm H2O 25 kPa 5.4 21.6 0.6-1.6 2.5-5.5 1.1-4.0 1.0-4.0 3.5-7.7
150˝ H2O 3750mm H2O 37 kPa 5.4 21.6 1.0-2.5 4.5-8.5 1.8-6.5 2.0-6.0 6.3-12.0
15 psid 1.0 kg/cm2 100 kPa 500 2000 0.5-1.0 2.0-5.0 0.7-3.5 0.7-1.4 2.8-7.0
30 psid 2.0 kg/cm2 200 kPa 500 2000 1.0-2.0 2.0-5.0 1.5-3.5 1.4-2.8 2.8-7.0
60 psid 4.0 kg/cm2 400 kPa 500 2000 2.0-4.0 3.0-6.0 3.0-4.5 2.8-5.6 4.2-8.5
100 psid 7.0 kg/cm2 700 kPa 1000 4000 4.0-10.0 11.0-20.0 7.0-15.0 6.0-14.0 16.0-28.0
200 psid 14.0 kg/cm2 1400 kPa 1000 4000 5.0-15.0 12.0-40.0 10.0-26.0 7.0-21.0 17.0-56.0
400 psid 28.0 kg/cm2 2800 kPa 1000 8000 10.0-20.0 20.0-60.0 15.0-40.0 14.0-28.0 28.0-84.0
600 psid 42 0 kg/cm2 4200 kPa 2000 8000 20.0-40.0 80.0-150.0 30.0-115.0 30.0-56.0 112.0-210.0
Values shown are for zero static working pressure.

NOTES:
Viton: Multiply Buna N value by 1.4
1 Switches may generally be set between 2 All deadbands are given in English units Teflon: Multiply Buna N value by 1.2
15% and 100% of nominal range on as shown in the nominal range column. Stainless Steel: Multiply Buna N value by 1.7
increasing pressure. Consult factory for Deadbands shown are for switches with Monel: Multiply Buna N value by 1.7
applications where setpoints must be Buna N diaphragm. Approximate dead- Dual Switch Element: Multiply single switch
lower. bands for optional diaphragms: element value by 1.6 for approximate
deadband.
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ORDER INFORMATION

B-SERIES PRESSURE AND DIFFERENTIAL PRESSURE SWITCH MODEL NUMBER:

To specify the exact switch desired, select entries from appropriate tables as shown in example below.

1 2 3 4 5

B 4 2 0 B X P K 600 PSI
1 – ENCLOSURE 2 – SWITCH ELEMENT SELECTION
Pressure switch, type 400, watertight enclosure Order Switch Elements
B4
meets NEMA 3, 4, 4X, 13 and IP66 requirements. Code UL/CSA Listed SPDT
Pressure switch, type 700, explosion-proof 20(7) Narrow deadband ac 15A, 125/250 Vac
B7 enclosure meets Div. 1 & 2, NEMA 7, 9 and IP66 21 Ammonia service 5A, 125/250 Vac
requirements. 22(6) Hermetically sealed switch, 5A, 125/250 Vac
Differential pressure switch, type 400, water- narrow deadband
D4 tight enclosure meets NEMA 3, 4, 4X, 13 and 23 Heavy duty ac 22A, 125/250 Vac
IP66 requirements. 24(1) General purpose 15A, 125/250/480 Vac
Differential pressure switch, type 700, explosion- 1⁄2A, 125 Vdc
D7 proof enclosure meets Div. 1 & 2, NEMA 7, 9 and 1⁄4A, 250 Vdc; 6A, 30 Vdc
IP66 requirements. 25(2) Heavy duty dc 10A, 125 Vac or dc,
1⁄8 HP, 125 Vac or dc

26(7) Sealed environment proof 15A, 125/250 Vac

3 – ACTUATOR SEAL 27 High temperature 300°F 15A, 125/250 Vac
Range 28(5) Manual reset trip on 15A, 125/250 Vac
Code Process increasing
and Temperature Vac. 0-600 1000 3000 29(5) Manual reset trip on 15A, 125/250 Vac
Material Limits °F(9) ˝ H2O psi psi psi decreasing
B – Buna-N 0 to 150 • • • • 31 Low level (gold) contacts 1A, 125 Vac
V – Viton 20 to 300 • • • 32 Hermetically sealed switch, 11A, 125/250 Vac
T – Teflon 0 to 150 • • • • general purpose 5A, 30 Vdc
42 Hermetically sealed switch, 1A, 125 Vac
S – 316L(8) 0 to 300 • •
gold contacts
P – Monel(8) 0 to 300 • • 50 Variable deadband 15A, 125/250 Vac
UL/CSA Listed Dual (2 SPDT)
61(7) Dual narrow deadband 15A, 125/250 Vac
4 – OPTIONS 62(7) Dual sealed environment 15A, 125/250 Vac
proof
Use table from page 9
63 Dual high temp. 300°F 15A, 125/250 Vac
64 Dual general purpose 15A, 125/250/480 Vac
1⁄2A, 125 Vdc
1⁄4A, 250 Vdc
5 – RANGE
65 Dual ammonia service 5A, 125/250 Vac
Select from table on page 4
67(4,6) Dual hermetically sealed 5A, 125/250 Vac
switch, narrow deadband
NOTES: 68(4) Dual hermetically sealed 11A, 125/250 Vac
1 Standard switch. switch, general purpose 5A, 30 Vdc
2 Not available with psid ranges. 71(4) Dual hermetically sealed 1A, 125 Vac
3 Dual switches are 2 SPDT snap-action switch, gold contacts
switches, not independently adjustable.
4 Not available with type 400 enclosure.
5 Not available with type 700 enclosure.
6 Estimated dc. rating, 2.5A, 28 Vdc (not
UL listed).
7 Estimated dc rating, 0.4A, 120 Vdc (not
UL listed).
8 Available on pressure only.
9 Ambient operating temperature limits –20
to 150°F, all styles, setpoint shift of ±1% of
range per 50°F temperature change is
normal.
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