Operation; Start, Stop, And Reset Commands; Command Override; Auto-Start/Stop - Danfoss VLT MCD 600 Operating Manual

VLT® Soft Starter MCD 600
Operating Guide

9 Operation

9.1 Start, Stop, and Reset Commands

The VLT® Soft Starter MCD 600 can be started and stopped via the digital inputs, remote LCP, communication network, smart card,
or scheduled auto-start/stop. The command source can be set via the Set-up Tools, or by using parameter 1-1 Command Source.
• The MCD 600 only accepts start and reset commands from the designated command source.
• The MCD 600 accepts stop commands from the designated command source, but can be forced to stop by opening the reset
input, or by opening the start/stop input during an auto-start/stop cycle.
• The programmable input can be used to override the selected command source (see parameter 7-1 Input A Function).

9.2 Command Override

The programmable input (DI-A, COM+) can be used to override the command source for situations where the normal control mech-
anism has been lost. Set parameter 7-1 Input A Function to the alternative control source (for example Command Override: Keypad).
While the input is active, the soft starter only accepts commands from the selected override source. To restore control to the com-
mand source selected in parameter 1-1 Command Source, reopen the input.

9.3 Auto-start/Stop

The soft starter can be configured to automatically start and/or stop the motor at a particular time, or run it in cycles of a specified
duration.
Start delay, restart delay, and auto-reset delay all apply to auto-start operation.

9.3.1 Clock Mode

The soft starter can start and/or stop the motor once per day.
For clock mode to operate:
•
Parameter 4-1 Auto-Start/Stop Mode must be set to Enable.
• Parameter 1-1 Command Source must be set to Clock.
• The reset input must be closed.
• The start input (START, COM+) must be active. This allows the soft starter to be stopped via the digital inputs in an emergency.
Clock mode operation is controlled by parameters 4-4 to 4-24.

9.3.2 Timer Mode

The soft starter can automatically stop the motor after a specified run-time, then restart it after a specified off (stopped) time. The
soft starter repeats the cycle while the start signal remains active.
For timer mode to operate:
• Parameter 4-1 Auto-Start/Stop Mode must be set to Enable.
• Parameter 1-1 Command Source must be set to Timer.
• The reset input must be closed.
• The first start must be commanded by a start signal.
Timer mode operation is controlled by parameters 4-2 to 4-3.

9.4 PowerThrough

PowerThrough allows the soft starter to control the motor even if the soft starter is damaged on 1 phase. The VLT® Soft Starter MCD
600 uses 2-phase control techniques to soft start and soft stop the motor.
PowerThrough does not support adaptive control soft starting or soft stopping. In PowerThrough, the soft starter uses constant
current soft starting and timed voltage ramp soft stopping. If Power Through is enabled,parameters 2-3 and 2-4 must be set appro-
priately.
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Operation
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