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Alarm Codes, Descriptions and Corrective Actions
µ
P-D Controller
CRR-20 & CRR-40, September 1999
Code
Description
Corrective Action
51
Unit Current Out-of-Range in COOL Mode
• Check for low supply power voltage.
(Check or Shutdown Alarm)
• Check the compressor current draw with a digital
• Indicates total unit current draw is not within
multimeter. Place unit in Full Cool mode using
acceptable limits when the unit is in Cool mode.
“REFRG FC HI” in the Refrigeration Test submenu.
Current draw on each leg should be within 0.2
NOTE: This is not a Pretrip test alarm.
amperes of each other. Current draw for compres-
sor only should be 7 to 11 amperes at 480V.
• Check evaporator fan motor current draw using
“AMPS EFH” and “AMPS EFL” in the Electrical Test
submenu. Current draw for evaporator fans only
should be 2 to 4.5 amperes at 480V. If current draw
is high, check for obstructions to evaporator airflow.
If current draw is low, check for a motor not operat-
ing.
• Check condenser fan motor current draw using
“AMPS CFH” in the Electrical Test submenu.
Current draw for condenser fan only should be 1 to
2.3 amperes at 480V. If current draw is high, check
for obstructions to condenser airflow. No current
draw indicates the motor is not operating.
• Check the evaporator fan and condenser fan motors
for free rotation and proper condition.
• Visually inspect evaporator fan, condenser fan and
compressor contactors.
• Check the output module and related circuitry using
“REFRG FC HI” in the Refrigeration Test submenu
to place the unit in Full Cool. Then confirm that out-
put LEDs AC11, AC12 and AC14 are ON.
• If current draw on each leg is not within 0.2 amperes
of each other during compressor current draw test,
check the current transformer. Turn unit OFF and
disconnect power supply. Disconnect plug on cur-
rent transformer and check the resistance of each
primary winding. Resistance for each winding
should be 43 +/- 0.5 ohms.
• Check the refrigeration system for excessively high
pressures.
Содержание CRR-20
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