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5.14 Two Speed Motor
The MCD 500 can be configured for control of dual speed Dahlander type motors, using a high speed contactor (KM1), low
speed contactor (KM2) and a star contactor (KM3).
NOTE
Pole Amplitude Modulated (PAM) motors alter the speed by effectively changing the stator frequency using external
winding configuration. Soft starters are not suitable for use with this type of two-speed motor.
When the soft starter receives a high speed start signal, it closes the high speed contactor (KM1) and star contactor (KM3),
then controls the motor according to the primary motor settings (parameters 1-1 through 1-16.)
When the soft starter receives a low speed start signal, it closes the low speed contactor (KM2). This closes Input A and the
MCD 500 controls the motor according to the secondary motor settings (parameters 7-1 through 7-16).
NOTE
If the MCD 500 trips on supply frequency (
16-5 Frequency
) when the high-speed start signal (7) is removed, modify the
setting of parameters 2-8 through 2-10.
Application Examples
MCD 500 Operating Instruction
44
MG17K402 - VLT
®
is a registered Danfoss trademark
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