Transfomer Grounding

[rucc722]

We are installing a 75KVA transformer to boost the incoming voltage from 208 to 480 for one piece of equipment. Since we are feeding the 208 into the secondary we are not producing a seperately derived neutral and are not sure where to ground the 480 volt side of the transformer? We have been told to ground B phase and or let the ground float? Any suggestions?

 

[infinity]

You have two options, ground one phase or leave the system ungrounded and install a ground detection device. If you choose to make a corner grounded system then any fused disconnect would not be permitted to have a fuse inline with the grounded conductor.

Welcome to the Forum.

 

[jim dungar]

Check with the equipment manufacturer. Many new generation (past 10 years or so) VFD's have filtering capacitors connected L-G and may require some specific setup considerations for non-wye installations.