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CRR-20 & CRR-40, September 1999
µ
P-D Controller
Alarm Codes, Descriptions and Corrective Actions
4-59
Code
Description
Corrective Action
57
Condenser Fan Current Out-of-Range (Pretrip)
• Check for low supply power voltage.
(Check or Shutdown Alarm)
• Check condenser fan current draw using “AMPS
• Indicates condenser fan current draw is not
CFH” in the Electrical Test submenu. Current
within acceptable limits when fan is operating.
draw should be 1 to 2.3 amperes at 480V. Current
draw on each leg should be within 0.2 amperes
• If alarm occurs during a Pretrip test, a
of each other.
dash (-) precedes the alarm code.
• If current draw is high, check condenser fan motor
for free rotation and proper condition. Air should be
out from the condenser fan grille.
• Visually inspect condenser fan contactor.
• If contactor does not energize, check output module
using “AMPS CFH” in the Electrical Test submenu.
Then confirm that output LED AC14 is ON.
• If current draw on each leg is not within 0.2 amperes
of each other during current draw test, check the
current transformer. Turn unit OFF and disconnect
power supply. Disconnect plug on current trans-
former and check the resistance of each primary
winding. Resistance for each winding should be 43
+/- 0.5 ohms.
58
Sensor Calibration Failure (Pretrip)
• Check for other sensor alarm codes, particularly
(Check or Shutdown Alarm)
codes 03, 05 and/or 07.
• Indicates the Return Air, Supply Air and
• Check for obstructions to evaporator airflow.
Evaporator Coil sensor temperatures are not
within acceptable limits after the evaporator
• Check sensor grade calibrations. Compare
fans have been ON for a specified time.
controller sensor grade setting in View Menu with
with grade shown on sensor identification decals.
• If alarm occurs during a Pretrip test, a
dash (-) precedes the alarm code.
• Check operation of evaporator fans using “AMPS
EFH” in the Electrical Test submenu. Then
visually inspect fans for proper rotation and
operation.
Содержание CRR-20
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