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CRR-20 & CRR-40, September 1999
µ
P-D Controller
Alarm Codes, Descriptions and Corrective Actions
4-51
Code
Description
Corrective Action
43
Frequency Out-of-Range Low
• Check the frequency of the supply power source
(Check Alarm)
and correct as required. If the unit is operating
on generator set power supply, check generator
• Indicates the frequency of the supply
speed.
power is low.
• If the frequency and voltage of the power supply are
correct but the controller displays 1/2 of the correct
reading, replace the power module.
44
Three Phase Current Imbalance
• Check supply power voltage on all three phases.
(Shutdown Alarm)
Voltage should be present on all three phases and
with 90% below or 110% above the rated voltage.
• Indicates the supply power current is
NOT equal within limits in each of the
• Check for open circuits in the three phase power
three phases.
circuits to the fans, heaters and compressor.
• Controller also generates alarm if phase
• Disconnect supply power and check resistance of
detection circuit was unable to determine
each heater leg. Correct open or shorted heaters.
correct phase rotation; or if phase contactor
ABC or CBA fails to pull in or release during
• Check operation of phase contactors using the
a Pretrip test.
“PS1” and “PS2” tests in the Controller Test
submenu.
• If the frequency and voltage of the power supply are
correct but the controller displays 1/2 of the correct
reading, replace the power module.
• Turn unit OFF and disconnect power supply.
Disconnect plug on current transformer and check
the resistance of each primary winding. Resistance
for each winding should be 43 +/- 0.5 ohms.
• If Alarm Code 10 is also present, check for an open
F11 fuse on the power module.
45
Frequency Out-of-Range High
• Check the frequency of the supply power source
(Check Alarm)
and correct as required. If the unit is operating on
generator set power supply, check the generator
• Indicates the frequency of the supply
speed.
power is high.
• If the frequency and voltage of the power supply are
correct but the controller displays 1/2 of the correct
reading, replace the power module.
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