Danfoss MCD500 Service Manual page 11

Troubleshooting
Symptom
AAC adaptive acceleration control, DC brake
2 2
and Jog functions not working
A reset does not occur after an Auto-Reset,
when using a remote 2-wire control.
Remote start/stop command is overriding Auto
Start/Stop settings when using remote 2-wire
control.
After selecting AAC the motor used an ordinary
start and/or the second start was different to
the first.
Non-resettable THERMISTOR CCT trip, when
there is a link between Thermistor input 05, 06
or when the motor thermistor connected
between 05, 06 is permanently removed.
Parameter settings cannot be stored.
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MCD 500 Service Manual
Probable Cause
- These features are only available with in-line installation. If the MCD 500 is installed inside
delta, these features will not operate.
- The remote 2-wire start signal must be removed and reapplied for a re-start.
- Auto Start/Stop function should only be used in HAND ON mode or in tandem with
HAND OFF mode, 3 and 4-wire control.
- The first AAC start is current limit so that the starter can learn from the motor character-
istics. Subsequent starts use AAC.
- The thermistor input is enabled once a link is fitted and short circuit protection has
activated.
Remove the link then load the default parameter set. This will disable the thermistor input
and clear the trip.
Place a 1k2 Ω resistor across the thermistor input.
Turn thermistor protection to 'Log only' (Par. 16-9).
- Make sure you are saving the new value by pressing the OK button after adjusting a
parameter setting. If you press BACK, the change will not be saved.
- Check that the adjustment lock (Par. 15-2) is set to Read/Write. If the adjustment lock is
on, settings can be viewed but not changed. You need to know the security access code
to change the adjustment lock setting.
- The EEPROM may be faulty on the Main Control PCB. A faulty EEPROM will also trip the
soft starter, and the LCP will display the message Par. Out of Range. Contact your local
supplier for advice.
®
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