User's Manual

Alarm Descriptions and Solutions
Liebert
®
DCP
™
64
6.0 ALARM DESCRIPTIONS AND SOLUTIONS
6.1 Alarm Descriptions
CALL SERVICE—Activated when Customer Input 1 is configured for “Call Service” and 24VAC is
applied to the input. This alarm is reset when the 24VAC is removed.
CONDENSATION DETECTED (optional)—Activated when water is detected at a cooling module.
A 24VAC signal is applied to the condensation input on the control board using a pair of twisted wires
or the alarm is sent via CANbus communication. When this alarm is active, the control will raise its
fluid control point by 4°F (2.2°C). This alarm will reset when the alarms is acknowledged and the
signal stops being sent from CANbus or condensation input. The alarm can also be reset by cycling
the power. The main power must be cycled to remove the 4°F (2.2°C) offset (not currently used).
CONTROL VALVE FAILURE—Activated when the chilled water control valve has been
commanded to open or close by the control and no change is detected by the valve position signal. The
alarm is reset when the main power is cycled.
CUSTOMER INPUT 1—Activated when a 24VAC signal is applied to the customer alarm input on
the control board. This alarm will reset when the 24VAC signal stops being sent from the customer
alarm input. WATER UNDER FLOOR, SMOKE DETECTED, CALL SERVICE, and COMP LOCK
PD are possible designations for this alarm; they are set with the Unit Code.
FAN FAILURE (optional)—Activated when a 24VAC signal is applied to the fan failure input on
the control board using a twisted pair of wires or the alarm is sent via CANbus communication. This
alarm will reset when the alarms is acknowledged and the signal stops being sent from CANbus or
fan failure input. The alarm can also be reset by cycling the power (not currently used).
HIGH CW TEMP—Activated when the Supply CW sensor reads the chilled water temperature
above the user-specified alarm setpoint. This alarm will reset when the reading from the fluid
temperature sensor drops 5°F (2.8°C) below the user-specified setpoint and the alarm has been
acknowledged.
HIGH DEW POINT—Activates when the calculated dew point at either Sensor A or B exceeds the
user-specified alarm setpoint. The alarm will reset when the calculated room dew point from both
Sensor A and Sensor B is 2°F (1.1°C) below the setpoint and the alarm has been acknowledged.
HIGH COOLANT TEMP—Activated when the coolant temperature sensor reads the coolant
temperature above the user-specified alarm setpoint. This alarm will reset when the reading from the
coolant temperature sensor drops 2°F (1.1°C) below the user-specified setpoint and the alarm has
been acknowledged.
HIGH TEMP SENSOR A—Activated when the reading from Sensor A is above the user-specified
alarm setpoint. The alarm will reset when the reading from Sensor A drops 2°F (1.1°C) below the
setpoint and the alarm has been acknowledged.
HIGH TEMP SENSOR B—Activated when the reading from Sensor A is above the user-specified
alarm setpoint. The alarm will reset when the reading from Sensor A drops 2°F (1.1°C) below the
setpoint and the alarm has been acknowledged.
LOSS OF FLOW PUMP 1—Activated when Pump 1 is commanded to run and the flow switch does
not sense flow. After attempting to start Pump 1 three times, the Liebert
DCP will automatically
switch to the other pump to establish flow. This alarm will reset when flow has been established on
Pump 1 and the alarm has been acknowledged.
LOSS OF FLOW PUMP 2—Activated when Pump 2 is commanded to run and the flow switch does
not sense flow. After attempting to start Pump 2 three times, the Liebert DCP will automatically
switch to the other pump to establish flow. This alarm will reset when flow has been established on
Pump 2 and the alarm has been acknowledged.
LOW MEMORY—Activated when the control board is low in memory resources. This alarm rests
automatically as soon as memory consumption falls below the threshold.
NOTE
Alarms must be acknowledged before they can be reset. To acknowledge or silence an alarm,
press the ALARM key one time. This will silence the alarm; the red LED will remain
illuminated until the alarm is reset.