1
Three-phase supply
2
Motor terminals
3
Relay A output
4
K1/K2 coil supply
5
Programmable input A
K1
Line contactor (Run)
K2
Line contactor (Brake)
A2
Zero-speed sensor
9.10 Pump Clean
The soft starter can perform a pump clean function before soft starting the motor. This can help dislodge debris from the impeller.
Pump clean starts the motor in reverse then forward direction, then stops the motor. Pump clean can be configured to repeat the
process up to 5 times. After the specified number of cleaning cycles, the soft starter performs the programmed soft start.
Pump clean operation is controlled by the start/stop input (START, COM+). Set a programmable input to pump clean (see
parameter
7-1 Input A Function
for details). Ensure that the input is closed when the start signal is applied.
300
200
100
400
50
25
0
e
7
7
h
a
7
8
7
.1
0
2
4
8
6
1
7
5
3
Reverse torque/
Forward current (%FLC)
Current
Torque
Time
Illustration 38: Pump Clean
1
Parameter 11-1 Reverse Torque
2
Parameter 11-2 Reverse Time
3
Parameter 11-3 Forward Current Limit
4
Parameter 11-4 Forward Time
5
Parameter 11-6 Pump Stop Time
6
Cleaning cycle
7
Parameter 11-7 Pump Clean Cycles
8
Programmed soft start
9.11 Reverse Direction Operation
The soft starter can control a reversing contactor to operate the motor in reverse direction. When reverse operation is selected, the
soft starter performs a soft start using the opposite phase sequence from normal operation.
Reverse operation is controlled by the start/stop input (START, COM+). Set a programmable input to reverse direction (
parameter
7-1 Input A Function
) and set an output to reversing contactor (
parameter 8-1 Relay A Function
).
The input must be closed when the start signal is applied. The soft starter keeps the reverse relay in the same state until the end of
the starting/stopping cycle.
The following example is a simple installation, but many different configurations are possible depending on the application require-
ments. Contact a local supplier for an application note showing more installation options.
N O T I C E
The first start after the direction is changed will be constant current.
N O T I C E
If phase sequence protection is required, install the reversing contactor on the output (motor) side of the soft starter.
AQ262141844215en-000401 / 175R1174
70 | Danfoss A/S © 2020.12
Operation
VLT® Soft Starter MCD 600
Operating Guide