Trip Messages - Danfoss MCD500 Service Manual

Troubleshooting

2.2 Trip Messages

This table lists soft starter's protection mechanisms and the
2 2
probable cause of the trip. Some of these can be adjusted
using parameter group 2 Protection and parameter group 16
Display
Battery/Clock
Current Imbalance
Excess Start Time
FLC Too High
Frequency
Heatsink Overtemp
Input A Trip
Inst Overcurrent
Internal Fault X
6
MCD 500 Service Manual
Possible cause/Suggested solution
A verification error has occurred on the real time clock, or the backup battery voltage is low. If the
battery is low and the power is off, date/time settings will be lost. Reprogram the date and time.
Related Pars.: 16-12
Current imbalance can be caused by problems with the motor, the environment or the installation,
such as:
- An imbalance in the incoming mains voltage
- A problem with the motor windings
- A light load on the motor
Current imbalance can also be caused by incorrect cabling between the external bypass contactor
and the soft starter or an internal problem with the soft starter, particularly an SCR that has failed
open circuit. A failed SCR can only be definitely diagnosed by replacing the SCR and checking the
starter's performance.
Related Pars.: 2-2, 2-3, 16-2
Excess start time trip can occur in the following conditions:
•
1-1 Motor Full Load Current is not appropriate for the motor
•
1-4 Current Limit
•
1-6 Start Ramp Time has been set greater than the setting for 1-9 Excess Start Time Setting
•
1-6 Start Ramp Time is set too short for a high inertia load when using Adaptive Acceleration
Control
Related Pars.: 1-1, 1-6, 1-4, 1-9, 7-9, 7-1, 7-6, 7-4, 16-7
The MCD 500 can support higher motor FLC values when connected to the motor using inside delta
configuration rather than in-line connection. If the soft starter is connected in-line but the
programmed setting for 1-1 Motor Full Load Current is above the in-line maximum, the soft starter will
trip at start.
Related Pars.: 1-1, 7-1
The mains frequency has gone beyond the specified range.
Check for other equipment in the area that could be affecting the mains supply (particularly variable
speed drives).
If the MCD 500 is connected to a generator set supply, the generator may be too small or could have
a speed regulation problem.
Related Pars.: 2-8, 2-9, 2-10, 16-5
Check if cooling fans are operating. If mounted in an enclosure, check if ventilation is adequate.
Fans operate during Start, Run and for 10 minutes after the starter exits the Stop state.
NOTE
Models MCD5-0021B to MCD4-0053B and MCD5-0141B do not have a cooling fan. Models
with fans will operate the cooling fans from a Start until 10 minutes after a Stop.
Related Pars.: 16-6
Identify and resolve the condition which caused Input A to activate.
Related Pars.: 3-3, 3-4, 3-5, 3-6, 3-7, 16-8
The motor has experienced a sharp rise in motor current, probably caused by a locked rotor condition
(shearpin) while running. This may indicate a jammed load.
Related Pars.: 2-6, 2-7, 16-4
The MCD 500 has tripped on an internal fault. Contact your local supplier with the fault code (X).
Related Pars.: None
®
MG.17.L4.02 - VLT is a registered Danfoss trademark
Protection Action, other settings are built-in system
protections and cannot be set or adjusted.