Danfoss VLT MCD 600 Operating Manual page 134

VLT® Soft Starter MCD 600
Operating Guide
Symptom Probable cause/suggested solution
Remote LCP shows The LCP is not receiving data from the control PCB. Check the cable connection.
Awaiting data
The soft starter does
•
not control the mo-
tor correctly during
•
start.
•
Motor does not
•
reach full speed.
Make sure that the motor starting parameters are appropriate for the application and that the inten-
ded motor starting profile is used. If a programmable input is set to Motor Set Select, check that the
corresponding input is in the expected state.
•
Soft stop ends too
•
quickly.
•
After selecting adap-
•
tive control, the mo-
tor used an ordinary
start and/or the sec-
ond start was differ-
ent to the first.
PowerThrough does
•
not operate when se-
lected
Parameter settings
•
cannot be stored.
•
USB full
•
•
USB missing A USB function has been selected in the menu, but the product cannot detect a USB drive. Check that the
USB drive has been inserted in the port.
File missing
•
•
130 | Danfoss A/S © 2020.12
Start performance may be unstable when using a low motor FLC setting (parameter 1-2 Motor Full
Load Current).
Install power factor correction (PFC) capacitors on the supply side of the soft starter. Disconnect the
capacitors during starting and stopping. To control a dedicated PFC capacitor contactor, connect the
contactor to a programmable relay set to Run.
High levels of harmonics on the mains supply side can affect the soft starter performance. If drives
are installed nearby, check that they are properly grounded and filtered.
If the start current is too low, the motor does not produce enough torque to accelerate to full speed.
The soft starter may trip on excess start time.
Check if the load is jammed. Check the load for severe overloading or a locked rotor situation.
The soft stop settings may not be appropriate for the motor and load. Review the settings.
If the motor is lightly loaded, soft stop has limited effect.
The first adaptive control start is constant current so that the soft starter can learn from the motor
characteristics. Subsequent starts use adaptive control.
The soft starter trips on Lx-Tx Shorted on the first start attempt after control power is applied. Power-
Through does not operate if control power is cycled between starts.
Make sure to save the new value by pressing [Menu/Store] after adjusting a parameter setting. If
pressing [Back], the change is not saved. The soft starter does not show a confirmation.
Check that parameter 10-7 Adjustment Lock is set to Read & Write. If the parameter is set to Read Only,
settings can be viewed but not changed.
The USB drive may not have enough free space available for the selected function.
The file system on the USB drive may not be compatible with the soft starter. The VLT® Soft Start-
erMCD 600 supports FAT32 file systems. The USB functions of the MCD 600 are not compatible with
NTFS file systems.
A USB function has been selected in the menu, but the required file cannot be found.
Save/load master parameters uses a file called Master_Parameters.par at the top level of the USB
drive. For these functions to work correctly, do not move or rename this file.
N O T I C E
Troubleshooting
AQ262141844215en-000401 / 175R1174