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Alarm Codes, Descriptions and Corrective Actions
µ
P-D Controller
CRR-20 & CRR-40, September 1999
Code
Description
Corrective Action
54
Defrost Current Out-of-Range (Pretrip)
• Check for low supply power voltage.
(Check or Shutdown Alarm)
• Check the heater element current draw using the
• Indicates total unit current draw is not within
“REFRG DFRST” test in the Refrigeration Test
acceptable limits when the unit is in Defrost
submenu. Current draw should be 7 to 10 amperes
mode.
at 480V. Current draw on each leg should be within
0.2 amperes of each other.
• If alarm occurs during a Pretrip test, a
dash (-) precedes the alarm code.
• Visually inspect the heater contactor.
• Check the output module and related circuitry using
“REFRG DFRST” in the Refrigeration Test submenu
to place the unit in Heat. Then confirm that ONLY
output LED AC7 is ON.
• If current draw on each leg is not within 0.2 amperes
of each other during heater current draw test, check
the current transformer. Turn unit OFF and discon-
nect power supply. Disconnect plug on current
transformer and check the resistance of each prima-
ry winding. Resistance for each winding should be
43 +/- 0.5 ohms.
Содержание CRR-20
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