Question

Is there a good way to do a master/follower with the VFDs?

Answer

Master/follower is a combination of AC drives and motors to get the follower motor to have a proportional speed of the master motor.

The GS2 and GS3 VFD's have an analog output 0-10 Volt for frequency.

This can be used for outputting an approximate speed control signal.

Error can be from 1% to 5 %, depending on the speed percentage; at lower speeds, the error is bigger.

You may offset the input frequency of the follower using the parameters P4-01 to 4-03

Just connect AO of the master into the analog input for frequency set point on the follower with a wire. Connect the ACM terminals from the master to the follower.

Program the analog output for frequency and the analog input for 0 10 Volt (P4-00 as 2)

If you want higher precision, consider the use of Durapulse drives with encoder feedback.
This will reduce the error to less than 0.5%.


In either case, this is not electronic gearing.

GS4 and GS20 both have 0-10V inputs.
GS20 allows single pulse input feedback which can be set up to command a slave drive which would be the most accurate way to do this

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FAQ Subcategory: None

This item was last updated on 2021-02-16
Document ID: 1076

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