7.5.2 Undercurrent
The MCD 500 can be configured to trip if the average
current of all three phases drops below a specified level
while the motor is running.
2-4 Undercurrent
Range:
Function:
20%
*
[0% -
100%]
Sets the trip point for undercurrent protection,
as a percentage of motor full load current. Set
to a level between the motor's normal working
range and the motor's magnetising (no load)
current (typically 25% to 35% of full load
current). A setting of 0% disables undercurrent
protection.
2-5 Undercurrent Delay
Range:
Function:
5 secs
*
[0:00 - 4:00
(min:secs)]
Slows the MCD 500's response to
undercurrent, avoiding trips due to
momentary fluctuations.
7.5.3 Instantaneous Overcurrent
The MCD 500 can be configured to trip if the average
current of all three phases exceeds a specified level while
the motor is running.
2-6 Instantaneous Overcurrent
Range:
Function:
400%
*
[80% - 600%
FLC]
Sets the trip point for instantaneous
overcurrent protection, as a
percentage of motor full load current.
2-7 Instantaneous Overcurrent Delay
Range:
Function:
0 secs
*
[0:00 - 1:00
(min:secs)]
Slows the MCD 500's response to
overcurrent, avoiding trips due to
momentary overcurrent events.
7.5.4 Frequency Trip
The MCD 500 monitors mains frequency throughout
operation, and can be configured to trip is the frequency
varies beyond a specified tolerance.
2-8 Frequency Check
Option:
Function:
Do not Check
Start Only
Start/Run
*
Run Only
Determines when the starter will monitor for a
frequency trip.
2-9 Frequency Variation
Option:
Function:
Selects the soft starter's tolerance for frequency
variation.
Running a motor outside its specified frequency for
long periods can cause damage and premature
failure.
±
2 Hz
±
5 Hz
*
±
10 Hz
±
15 Hz
2-10 Frequency Delay
Range:
Function:
1 sec
*
[0:01 - 4:00
(min:sec)]
Slows the MCD 500's response to
frequency disturbances, avoiding trips
due to momentary fluctuations.
NOTE
If the mains frequency drops below
35 Hz or rises above 75 Hz, the
starter will trip immediately.
2-11 Restart Delay
Range:
Function:
10
secs
*
[00:01 -
60:00
(min:secs)]
The MCD 500 can be configured to force
a delay between the end of a stop and
the beginning of the next start. During
the restart delay, the display shows the
time remaining before another start can
be attempted.
NOTE
The restart delay is measured from
the end of each stop. Changes to
the restart delay setting take effect
immediately.
2-12 Motor Temperature Check
Option:
Function:
Selects whether the MCD 500 will verify the
motor has sufficient thermal capacity for a
successful start. The soft starter compares the
motor's calculated temperature with the
temperature rise from the last motor start and
only operates if the motor is cool enough to start
successfully.
Do not
Check
*
Check
Programming
MCD 500 Operating Instruction
MG17K402 - VLT
®
is a registered Danfoss trademark
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