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CRR-20 & CRR-40, September 1999
µ
P-D Controller
Alarm Codes, Descriptions and Corrective Actions
4-53
Code
Description
Corrective Action
49
Pulp Sensor Failure (Option)
• Check the sensor by selecting it using the View
(Check Alarm)
menu. If PULP1 display shows [- - - -], the sensor
is defective or the circuit is open or shorted.
• Indicates a problem exists with this sensor
or its wiring. The sensor is reading out-of-
• Check the sensor by substitution. Be sure the
range; or appears to be open or shorted.
sensor polarity is correct.
• This sensor REQUIRES ice bath calibration.
• Continuity check circuit wiring using a high quality
multimeter. Be sure to maintain the correct polarity
or the sensor will not work.
NOTE: Do NOT use a test light or other instru-
ment; or controller damage may result.
50
Compressor Current Out-of-Range
• Check for low supply power voltage.
(Pretrip and Normal Operation)
(Check or Shutdown Alarm)
• Check the compressor current draw with a digital
multimeter. Place unit in Full Cool mode using
• Indicates compressor current draw is not within
“REFRG FC HI” in the Refrigeration Test submenu.
the high or low limits when the compressor
Current draw on each leg should be within 0.3
operates alone.
amperes of each other.
• If alarm occurs during a Pretrip test, a
• Visually inspect the compressor motor overloads
dash (-) precedes the alarm code.
and compressor contactor.
• Also occurs if controller determines that
• Check the output module and related circuitry if the
the compressor motor overload opened
compressor contactor does not energize. Place unit
in Full Cool mode using “REFRG FC HI” in the
Refrigeration Test submenu. Then check to see that
compressor output LED AC11 is ON. Check related
unit wiring as necessary.
• If current draw on each leg is not within 0.3 amperes
of each other, check the current transformer. Turn
unit OFF and disconnect power supply. Disconnect
plug on current transformer and check the resis-
tance of each primary winding. Resistance for each
winding should be 43 +/- 0.5 ohms.
• Check the refrigeration system for excessively high
pressures that could cause high compressor current
draw.
Содержание CRR-20
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