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Display
Possible cause/Suggested solution
Motor Thermistor
The motor thermistor input has been enabled and:
- The resistance at the thermistor input has exceeded 3.6 k
Ω
for more than one second.
- The motor winding has overheated. Identify the cause of the overheating and allow the motor
to cool before restarting.
- The motor thermistor input has been open.
NOTE
If a valid motor thermistor is no longer used, a 1.2 k
Ω
resistor must be fitted across
terminals 05, 06.
Related Parameters:
16-9 Motor Thermistor
Network Comms
The network master has sent a trip command to the starter, or there may be a network communi-
cation problem.
Check the network for causes of communication inactivity.
Related Parameters:
16-11 Network/Comms
Parameter out of Range
- A parameter value is outside the valid range.
The starter will load the default value for all affected parameters. Press [Main Menu] to go to the
first invalid parameter and adjust the setting.
Related Parameters: None
Phase Sequence
The phase sequence on the soft starter's input terminals (L1, L2, L3) is not valid.
Check the phase sequence on L1, L2, L3 and ensure the setting in
2-1 Phase Sequence
is suitable
for the installation.
Related Parameters:
2-1 Phase Sequence
Power Loss
The starter is not receiving mains supply on one or more phases when a Start Command is given.
Check that the main contactor closes when a start command is given, and remains closed until the
end of a soft stop.
If testing the soft starter with a small motor, it must draw at least 2% of its minimum FLC setting
on each phase.
Related Parameters: None
Starter/Comms
- There is a problem with the connection between the soft starter and the optional communi-
cations module. Remove and reinstall the module. If the problem persists, contact your local
distributor.
- There is an internal communications error within the soft starter. Contact your local distributor.
Related Parameters:
16-10 Starter/Comms
Thermistor Cct
The thermistor input has been enabled and:
- The resistance at the input has fallen below 20
Ω
(the cold resistance of most thermistors will
be over this value) or
- A short circuit has occurred. Check and resolve this condition.
Check that a PT100 (RTD) is not connected to 05, 06.
Related Parameters: None.
Time - Overcurrent
The MCD 500 is internally bypassed and has drawn high current during running. (The 10 A
protection curve trip has been reached or the motor current has risen to 600% of the motor FLC
setting.)
Related Parameters: None
Undercurrent
The motor has experienced a sharp drop in current, caused by loss of load. Causes can include
broken components (shafts, belts or couplings), or a pump running dry.
Related Parameters: 2-4, 2-5, and 16-3
Unsupported Option
The selected function is not available (e.g. jog is not supported in inside delta configuration).
Related Parameters: None
Table 9.1
Troubleshooting
MCD 500 Operating Instruction
72
MG17K402 - VLT
®
is a registered Danfoss trademark
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