VFD output cable size

[ptonsparky]

What protects the output conductors from short circuit and ground fault?


Sent from my iPhone using Tapatalk

The raceway and installation by qualified persons protect the conductors from physical damage.

Once they are damaged the VFD detects and removes power from them thus limiting the damage to both the conductors and the drive itself.
SC & or GF due to motor insulation failure is detected by the VFD which again removes power.

What are we missing that you don't seem to understand?

 

[Besoeker3]

How would one size the vfd output cables between the vfd and the motor? Which NEC 2017 Article and section apply here?

We don't. They are self protecting. We do protect the input conductors including earth ground faults.. This is what the majority of our drive systems do and having been doing for about 30 years. Do no try not to over complicated this.

 

[Krusscher]

https://forums.mikeholt.com/threads/ocpd-for-vfd-circuit.109814/ Reading through this might give you a better understanding especially jraef's post