We have 120v three phase delta systems that were installed as ungrounded over 50 years ago.
The systems were converted to 'grounded' .
One method was to ground phase A. The neutral of all receptacles must be connected to phase A.
Is it acceptable to use a zig-zag grounding transformer to achieve a grounded system.?
If yes, what about receptacle polarity? Each pole
would have 69v to ground.
The systems were converted to 'grounded' .
One method was to ground phase A. The neutral of all receptacles must be connected to phase A.
Is it acceptable to use a zig-zag grounding transformer to achieve a grounded system.?
If yes, what about receptacle polarity? Each pole
would have 69v to ground.