Search FAQs

Is it possible to run an 480V Altivar drive with 480V supply but their motor is only rated for 230V?

Issue:
Running a 230V motor with an 480V Altivar drive and supply.

Product Line:
All 480 Volt Altivar drives.

Environment:
All models rated for 480V input and output, All serial numbers.

Cause:
Incompatible motor/drive selection made

Resolution:
It is not recommended to operate a 208/230V motor from a 480V drive. It is possible if certain conditions are met to do so temporarily however it is strongly advised that the correct voltage drive/motor be installed.

A 230V motor requires roughly twice as much current as a 460V motor to produce the same amount of horsepower and this can exceed the rating of the 480V drive. Also, you must set the rated motor voltage in the drive to match the actual rated voltage of the motor. Refer to the programming manual for your particular drive for instructions to change this parameter. Also, be aware that the output of the drive is not a true sine wave. It is a pulse width modulated signal generated by the IGBTs and each of these pulses will be at the voltage of the DC bus. On a 230V drive the DC bus voltage is typically around 325 VDC. On a 480V drive this voltage is typically around 680VDC. This increased voltage may cause damage to your motor. If a 480V drive must be used on a 230V motor temporarily, a 5% load reactor should be placed between the output of the drive and the motor to help reduce this voltage. In all cases it is advised to replace the motor or drive as needed to a selection that is compatible. Note that a 480V drive can not operate with 230V input so if 480V supply is all that is available then the drive must be rated for 480V. In this situation it would be best to replace the motor with one rated for 460V.