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This FAQ has been written for NEAL (North East Africa and Levant) region. If you are looking for information for another region, please select the correct country from the top-left dropdown in the page and 'Navigate to Browse FAQs' in the Support menu.

What are the guide lines for parallel motor operation through a single VSD ?

The key point for connecting motors in parallel & controlling by a single drive is that the drive nominal current must be >= greater than or equal to the sum of the currents of the motors to be controlled (also 10% can be added as safety factor) In drive > In1 + In2...Inx

Also refer to the below restrictions to be followed:
1- Motor thermal protection is not guaranteed by drive. So, we recommend to install Thermal overload relay in accordance with motor rating individually for each motor in between VFD output and Motor.
Kindly find attached a rough schematic for the conections (indicating only the overload)

2-Total cable length would be the sum of individual cable distance form drive to motor. So, while installing it is important to know the total cable distance at your site of installation. If increased you should go for motor choke/sinus filter according to the length

3- Use V/F

4- The auxiliary contacts on the overload relays should be connected in series and connected to an Emergency Stop so that if one overload opens, the drive shuts down