•
•
N O T I C E
TVR soft starting is not suitable for high-inertia loads (such as fans), which require a high level of voltage to accelerate the load.
N O T I C E
For multiple motors of the same size, and/or mechanically coupled loads, use constant current starting.
For a timed voltage ramp start, the following are typical values and can be adjusted to suit a specific application:
Add the FLC value of all the connected motors. Use this combined value to set
parameter 1-2 Motor Full Load Current
.
N O T I C E
The combined value must not exceed the soft starter rating.
Set
parameter 2-3 Initial Current
to 100%,
parameter 2-4 Current Limit
to 500%, and set the ramp time as required (
parameter 2-2
Start Ramp Time
).
3
6
5
4
2
1
e7
7h
a8
19
.1
0
Illustration 32: Example of TVR
1
Initial current (parameter 2-3)
2
Curret limit (parameter 2-4)
3
Start ramp time (parameter 2-2)
4
Full voltage
5
Motor 1 current
6
Motor 2 current
9.8.5 Adaptive Control for Starting
In an adaptive control soft start, the soft starter adjusts the current to start the motor within a specified time and uses a selected
acceleration profile.
N O T I C E
The soft starter applies the current limit on all soft starts, including adaptive control. If the current limit is too low or the start
ramp time (set in
parameter 2-2 Start Ramp Time
) is too short, the motor may not start successfully.
AQ262141844215en-000401 / 175R1174 | 65
Danfoss A/S © 2020.12
Operation
VLT® Soft Starter MCD 600
Operating Guide