Grounding Requirements
Grounding Requirements
(OP)
Does a 240V delta load from a transformer 480/240 3W transformer need to be grounded? I am looking for code references if possible (I can find wye references, but not for delta secondaries).
Thanks.
Thanks.






RE: Grounding Requirements
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Grounding Requirements
RE: Grounding Requirements
So by "480/240" you mean a 480 V primary and a 240 V secondary?
RE: Grounding Requirements
What I am hearing (reading) is that the equipment grounds for motors and other equipment should be connected back to the main system ground....
Correct me if I am wrong....else, thanks for your help.
RE: Grounding Requirements
The short answer is yes. The long answer is to read NEC Article 250 Section VI on Equipment Grounding conductors. There are some exceptions.
RE: Grounding Requirements
System grounding means connecting one of the supply conductors to ground. A three wire 240 volt delta system may be run ungrounded. However I believe that ground fault detection is required.
respectfully
RE: Grounding Requirements
RE: Grounding Requirements
Many transformers with 240 V delta windings have one winding with a center tap that can be grounded to provide 120V phase to ground on two phases, with the third leg (wild leg) at 208V phase-ground. This would be the best way to ground this application.
RE: Grounding Requirements