Replacing The Communication Module; Figure 24 - St 700 Standard Transmitter - Pwa Replacement - Honeywell ST 700 User Manual

6.4

Replacing the Communication Module

The Communication module includes a connector to the sensor ribbon cable and a connector to the
optional Display module. This section includes the procedure to replace the Communication module.
The transmitter does not have to be removed from service to replace the Comm Module
Please take appropriate steps to avoid ESD damage when handling the
Communication and Display Module assemblies
Refer to Figure 24 for parts locations.
Figure 24 – ST 700 Standard Transmitter - PWA Replacement
1. Turn OFF Transmitter power (Power removal is only required in accordance with area safety
approvals. Power removal is only required in Class 1 Div 1 Explosion-proof and Class 1 Div
2 environments).

When removing the Communications Module with power applied, the loop will go to
0V. Likewise, installing a Communications Module into a transmitter with power
applied will cause the loop output value to go to 12ma for several seconds then the
loop output value will go to the configured value based on the PV input.

Installing a Display Module into a powered transmitter may cause a temporary upset
to the loop output value.
2. Loosen the end cap lock, and unscrew the end cap from the electronics side of the Transmitter
housing.
3. If equipped with a Display module, carefully depress the two tabs on the sides of the Display
Module, and pull it off.
4. If necessary, unplug the interface connector from the Communication module. Do not
discard the connector.
5. Loosen the two retaining screws, and carefully pull the Communication module from the
Electronics compartment.
Revision 8.0
ST 700 SmartLine Pressure Transmitters User's Manual
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