Operating instructions

AMC-DTR Sensor Transmitter User Manual
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6.2 Alarm Operation
AMC-DTR’s have front panel LED indicators for Alarm 1, Alarm 2 and Alarm 3. An optional
DTR-10-0234 Relay/Modbus board adds K1, K2 & K3 relays for these alarms.
CAUTION:
AMC-DTR Alarm LED indicators function even without the presence of the DTR-10-0234 Relay
option. With 2-Wire 4-20mA operation, to conserve power, alarm LED’s only flash during alarm
events. With 3-Wire 4-20mA operation, alarm LED’s flash when new, and become steady after
an operator ACKNOWLEDGE - pressing the UP/RESET key.
6.2.1 ALARM 3 – Understanding Fault / Level Operation
The “A3” alarm is typically dedicated to FAULT conditions indicating sensor failures or “out of
measurement range” conditions. However, some applications require a third level alarm. The
A3 menu is identical to A1 & A2 and may be set to trip at an upscale level value. A3 WILL
ALSO TRIP WITH MISSING OR FAILED SENSORS REGARDLESS OF THE LEVEL VALUE!
CAUTION:
Missing or failed sensors always trip Alarm 3 and relay K3 (if equipped). This is true even with
A3 configured as a level alarm and it must be accepted that A3 level alarm events might be
caused by the monitored level, or, by a missing or failed sensor.