Re: 240 volt 4 wire versus 3 wire connections
I think what Bennie is talking about is 208V and 240V equipment like a water heater doesnt require a neutral conductor for proper operation and that the EGC will have zero current and only act as an effective fault path.
However, this is not the case for 208V and 240V equipment that has line to neutral loads like dryers and ranges.
The topis starter made it clear that the equipment requires 4 wires. Two ungrounded, a neutral, and a grounding conductor. The unit must have line to neutral loads along with a line to line load, and therefor requires a return conductor that is not connected to the metallic parts of the circuit and equipment.
If the installer bonds the white and green together as suggested in the post, the line-toline loads will not be the problem, but the line-to-neutral loads will be. This current will be present on the metallic case of the equipment, and any other metallic parts of the system. This is a clear hazrd and code violation.
[ July 03, 2003, 07:22 PM: Message edited by: bphgravity ]