Model 510 & 520 Digital Trim Kit

Installation Manual

199 Fire Tower Drive

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98510/520TRIMKIT Rev. C
 DIGITAL TRIM

Viatran Instruments are factory calibrated. However, because of mounting or other effects, you
may wish to “re-trim” the transmitter. For this reason, 510 & 520 transmitters are equipped with
digital potentiometers which allow the user to adjust the zero and span. A pc with a parallel port
running Windows 2000, NT, or XP and loaded with the “Viatran Calibration Software” is needed to
perform a digital trim. The software is available from Viatran. You will also need a power supply
and ammeter to set up a current loop and read the transmitter output as you adjust the zero and
span.

SOFTWARE INSTALLATION

The “Viatran Calibration” installation disk includes the setup application, SETUP list file, and an
additional zip file. If your computer is running Windows XP, you must have administrative rights to
install this software. You do not need administrative rights to run the application after it is
installed.

Insert the installation CD in the computer. Select “run” from the “Start” menu and browse for the
“setup” application on the drive holding the installation CD. Click “ok” to begin the installation
process. Follow the prompts. NOTE: Abort the procedure if you are asked to overwrite any files.
Do not overwrite old versions! Contact the factory for assistance. You must reboot the computer
before using the software. The software is accessible from the Start menu “Programs” directory as
“510 Calibration Software”.

PC TO TRANSMITTER CONNECTIONS

Remove the adapter and secure it to the sensor housing using one screw as shown below:

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98510/520TRIMKIT Rev. C
Insert the 5-pin serial connector cable as shown below. The white mark on the cable must be
positioned closest to the outer edge of the PC board for proper operation.

Connect the other end of the serial interface cable to the parallel port of your PC.

SETTING UP THE CURRENT LOOP

The transmitter must be powered on to perform a digital trim. Power is applied to the Model 510 &
520 through the connector on the adapter assembly. The current loop is demonstrated below.

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98510/520TRIMKIT Rev. C
 COMMUNICATION TEST

The calibration software may be started by clicking the program link. The link is accessible from
the Start menu “Programs” directory as “Viatran Calibration Software”. The following screen will
appear when the software is started.

The software must be able to send signals to and receive signals from the transmitter to perform a
digital trim. The menu item “Communication Test” should be clicked to verify that the software is
able to establish communications with the transmitter. A text box with a “Pass” or “Failed” message
will be displayed. If the unit failed, the software cannot communicate with the transmitter. The
transmitter to pc and current loop setups should be checked. Make sure that the power supply is
on! The transmitter must be powered when performing a digital trim. If the unit still fails the
communication test, the software installation may require additional steps for your computer.
Check the “ReadMe” file that came with the software.

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98510/520TRIMKIT Rev. C
 FULL SCALE TRIM

The buttons labeled “up” and “Down”, located on the right side of the screen below the text
“COARSE SPAN” and “FINE SPAN”, are used to adjust the transmitter’s span. Full scale is the
pressure at which the transmitter generates a 20 milliamp output. The span is the difference
between the full scale and zero values. Setting the full scale output adjust the span.
PLEASE NOTE: A “SPAN” adjustment should only be performed with the full scale pressure applied
to the sensor. When full scale pressure is applied to the unit, the “Up” and “Down” buttons may be
used to increase and decrease the output, respectively. The output will step up or down in
increments as the buttons are pressed and, as such, it may not be possible to set exactly 20.00
milliamps. The output should be adjusted to be as close to 20 milliamps as possible, using the
coarse and fine span adjust buttons. When this is achieved, the “Store Settings” button must be
pressed. If the settings are not stored, the unit will not remember the new settings when the power
is cycled. If the unit does not adjust, the software installation may require additional steps for your
computer. Check the “ReadMe” file that came with the software.

Viatran Corporation
199 Fire Tower Drive
Tonawanda, New York 14150 USA
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98510/520TRIMKIT Rev. C