Technical FAQs

Ask a Question

How does an ATV12 series drive detect a ground short circuit fault?

Issue:
How is a ground short circuit fault detected in the ATV12 series.

Product line:
ATV12 series drives

Environment:
All models, All serial numbers.

Cause:
Clarification of drive characteristics needed by customer.

Resolution:
The three phase output of the drive can be considered 3 parallel paths, in relation to the DC bus.  In a parallel circuit, the total current flow is equal to the sum of the current flow in each branch.   When the drive is sending power to the motor, current flows out of one phase of the output, through the motor, and back into the other two phases of the drive.  As the phase rotates, current flow alternates direction to generate a rotation magnetic field inside the motor.  The drive measures the current flow on each output phase and looks at the difference between the current flowing out of the drive and the current returning to the drive from the motor.  The difference should be zero.  If it is not then that means that some of the current flow is taking a different path and is not returning through the motor to the drive.  The drive detects this as a ground short circuit fault.
Was this helpful?
What can we do to improve the information ?