Specifications

MCD3000 Series
MG.15.A4.22 - VLT is a registered Danfoss trademark 45
Fault Procedure
• Restart delay active. A start cannot
be initiated within the programmed
restart delay period. (Refer to Par.
15 Restart Delay for details).
• Auto-Reset active. If there has been
a trip and the Auto-Reset function
has been turned ON, the MCD3000
will be in Auto-Reset mode. This
includes a reset delay period, during
which a start cannot be initiated
without first resetting the starter.
(Refer to Par. 39,40, 41 & 42
Automatic-Reset for details).
Starter will
not enter
program
mode.
• Starter is running. Stop the starter
and try again.
• Incorrect or no control supply
voltage. Ensure the correct supply
voltage is applied. (Terminals A1,A2
& A3).
Symptom Cause & Action
Program
settings
cannot be
made.
• Read Only mode is active. Set Par.
48 Parameter Lock to Read/Write.
• Incorrect programming procedure.
User programmed settings must be
stored using the [CHANGE
DATA/OK] button before moving to
another parameter.
DOL or
uncontrolled
start.
• Power factor correction capacitors
connected to starter output.
Remove any PFC from the starter
output. Check for damage to the
soft start power modules by
performing the SCR Test as detailed
in the next section of this manual.
• Damaged soft starter power
modules. Check the soft start power
modules by performing the SCR
Test as detailed in the next section
of this manual.
• Damaged soft starter firing circuit.
Check the soft start firing circuit by
performing the Firing Circuit Test as
detailed in the next section of this
manual.
Motor will
not
accelerate
to full speed.
• Insufficient start current. Check the
load. Increase the start current
supplied to the motor by adjusting
Par. 2 Current Limit.
Symptom Cause & Action
Erratic
Motor
Operation
and tripping.
• Very small motor being controlled by
a large starter. The current drawn by
very small motors sometimes used
to test soft starter installations can
be too low to latch the soft starter
SCRs. Increase motor size.
MCD3000
display
shows an ’h’
h
The [START] button on the MCD3000
local control panel is stuck. Release the
button to restore normal operation.
Soft stop
function
ceases
before the
set ramp
time.
The MCD3000 soft stop function has
significantly reduced the output voltage
to the motor without detecting any
reduction in motor speed. This indicates
a no, or very light load condition that
makes further control of the voltage
ineffective, hence the soft stop function
has been halted.
■ Test and measurement procedures
The following tests and measurements can be used to
verify starter operation.
START PERFORMANCE TEST;
This procedure tests for correct operation of the
MCD3000 during start.
• Calculate the expected start current by multiplying
Par. 1 Motor FLC by the Par. 2 Current Limit or, if
the secondary parameter set is being tested Par.
25 Motor FLC by the Par. 26 Current Limit.
• Initiate a start and measure the actual start
current.
• If the measured start current is equal to the
calculated current the starter is performing
correctly.
RUN PERFORMANCE TEST;
This procedure tests for correct operation of the
MCD3000 during run.
• Measure the voltage across each phase (L1-T1,
L2-T2, L3-T3) of the soft starter. A voltage drop of
approximately 2 VAC or less indicates the starter
is performing correctly.
POWER CIRCUIT TEST:
This procedure tests the MCD3000 power circuit
including the SCR, firing loom and printed circuit
board.