AERCO Control System (ACS) - Manual (Page 82)

MC2: 04/23/13 Page 82 of 144
GF-131
AERCO Control System (ACS)
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, New York 10913 • Phone: 800-526-0288
Installation, Operation, and Maintenance Manual
OMM-0081_0D
Table 5-1: Fault Messages (Cont.)
Fault Message Description & Possible cause
CURRENT LOOP
ERROR
The 4-to-20-mA remote input signal has dropped below 3 mA, or the
signal is not present at the ACS.
FAIL SAFE MODE
ACTIVATED
This message indicates that the ACS is operating in the Fail Safe
(Constant Setpoint) mode.due to sensor loss or signal loss.
MODBUS TIMEOUT
ERROR
Displayed during Modbus Remote Setpoint operation when the ACS is
functioning as a Slave to an EMS Master. Error indicates that the
Network Timeout has expired.
NETWORK DISABLED
MODBUS LISTEN
Displayed during Modbus operation when the “FORCE LISTEN
ONLY” Modbus diagnostic command is sent to the ACS Slave by the
controlling Master, thereby disabling normal Modbus Network
communication. It indicates that the ACS is listening for the
“RESTART COMMUNICATIONS OPTIONS” diagnostic command
required to restart normal Modbus communication. The ACS will
operate in the Fail Safe mode during this period.
VALVE POSITION
ISSUE ERROR
For Option 1 or Option 2, the motorized valve has not reached its
expected position on time. Valve wait time has been exceeded.
FAULT ALARM
BOILER ERROR
A boiler connected to the ACS is in fault.