Advertisement
Available languages
Available languages
2 I Fault diagnosis
Fault diagnosis
In case of malfunctions during compressor operation we recommend
to prepare a measurement record for aiding the fault search:
Pressure measurement: Discharge side, suction side,
oil pressure
Temperature measurement: Compressor casing,
discharge end temperature, suction gas overheating
According to the expected cause of the fault it may be necessary
to check the electrical systems for faults in the control.
In order to localize the causes of operating malfunctions as easy
as possible we have compiled the following table with suggestion
for remedying compressor malfunctions.
Compressor stand still
Compressor does not start
Problem
Control circuit is interrupted
Main- or ontrol circuit is
switched
off
Main- or control circuit is wired
incorrectly
Bridges / connection cable in
terminal box is wired incorrectly
Incorrect voltage
Phase or neutral is missing
Overload / motor safety is swit-
ched off
4
Possible cause
Main- or control fuse is switched off or
tripped
- Setting / selection incorrect
- Motor overloaded
- Undervoltage
- Starter contacts / shorted contacts /
earthed contacts
Cut off through:
- Low pressure switch
- High pressure switch
- Heat protection thermostat
- Control thermostat
- Other safety elements
Setting / selection incorrect
Function / drive not working
Motor overloaded
Undervoltage
Short circuit ON / OFF
Starter contacts / shorted contacts /
earthed contacts
Function faults - Symptoms
Function faults arising most frequently and their symptoms are:
Compressor stoppage, compressor cutoff
- Compressor does not start
- Compressor starts and then stops again
Refrigerant performance too low
Too high compressor temperature
Oil problems
Abnormal compressor running noise
Remedy
Replace fuse
Determine and remove the cause
Locate the interruption in the circuit
and remove
switch on
wire correctly
wire correctly
connect to correct voltage
connect
Check design
Check cable, electronic system
Check operating conditions
Determine and remove the cause
Check control
Check motor for winding damages / check
shorted contacts
Advertisement
