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Alarm Codes, Descriptions and Corrective Actions
µ
P-D Controller
CRR-20 & CRR-40, September 1999
Code
Description
Corrective Action
46
USDA 1 Sensor Failure (Option)
• Check the sensor by selecting it using the View
(Check Alarm)
menu. If USDA1 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.
47
USDA 2 Sensor Failure (Option)
• Check the sensor by selecting it using the View
(Check Alarm)
menu. If USDA2 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.
48
USDA 3 Sensor Failure (Option)
• Check the sensor by selecting it using the View
(Check Alarm)
menu. If USDA3 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.
Содержание CRR-20
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