4/20 Ma Loop Test - Honeywell EC-FX-NH3 Instruction And Installation Manual

4/20 mA Loop Test

NOTE: This test is recommended especially for PLC operations (non-
Honeywell readout/alarm unit).
NOTE: This test will not automatically time out. You must force the unit into
normal operation.
•
Start: Place meter leads on Test (+) and Test (—). Press button five times within a
two- or three-second period of time. The voltmeter should read approximately 220
mV (equal to 22.0 mA output). Verify full-scale signal at PLC. NOTE: some PLCs
limit input to 20 mA. Blink sequence will be:
•
Exit: Press and hold button for one second. Sensor will exit test and return to
normal operation.
NOTE: This test will not automatically time out. You must force the unit into
normal operation.
Full Scale Test: This test will verify that the full-scale output of the
sensor is also achieved at the PLC.
Signal Fault Test: This test will simulate one of many sensor fault
conditions in which the transmitter will send 0.5 mA to the control
panel. To check for downscale fault verification, press button for
one second (voltmeter should read approximately 5 mV (equal to
0.5 mA output). Verify downscale fault indication at PLC. Blink
sequence will be:
PLC and monitoring equipment should indicate Fault at this extremely
low signal output, (i.e., Honeywell Analytics recommends fault
indication on any signal below 1.5 mA.)
OPERATOR MANUAL
Continuous ON
Fast blink
Continuous ON
Medium blink
Continuous ON
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