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Eric Shuman
11-18-2009, 08:07 AM
This house has a panel downstream of the service entrance being used as the service disconnect for the air conditoner condensers. The disconnect switches in this panel are also the over current protection for the a/c units (two properly sized circuit breakers). There is another larger circuit breaker at the se panel that provides the protection for this panel. I know that here typically is no neutral for 240 branches for a/c units. My question is, with this panel being used not only as a service disconnect but also over current protection, should the neutral feed from the se panel be connected to an isolated bus? With the overcurrent protection, does the panel at this point become a "sub-panel" (sorry Jerry) requiring four wire service? They have cut the neutral off and taped it up, see photo below.

Jerry Peck
11-18-2009, 07:09 PM
This house has a panel downstream of the service entrance being used as the service disconnect for the air conditoner condensers.

With the overcurrent protection, does the panel at this point become a "sub-panel" (sorry Jerry)

Not unless you put it in a submarine.

Not sure why you felt obligated to insert an unnecessary term which seems to have confused you when you already clearly stated what it was.

"panel downstream of the service entrance"

What is not to understand about that?

That means the neutral IS REQUIRED TO NOT be bonded to ground as it is, by your own statement, "downstream of the service" equipment.

The question then becomes: Is this ONLY being used as a disconnect for 240 volts?

If so, then no neutral is required, and if not required it is not required to be connected. And if not required to be, and not, connected - then it is simply a 240 volt panel.

You only need the neutral if the panel is a 120 volt / 240 volt panel.

Let's say they inserted another breaker into that remaining spot to use for anything, such as a receptacle ... in that case, the neutral would be required, and being required, it would also be required to be isolated from ground.

A 240 volt circuit only requires 2 hot conductors and 1 ground conductor.

John Steinke
11-20-2009, 06:07 AM
So the guy ran a wire he didn't need, left you enough wire to work with, and taped it off; what's he supposed to do?

It's rather nice of him to do so; there's no telling what equipment will be used for replacement, and the neutral just might be needed then. He also avoided any confusion as to whether the white wire was really a 'hot' wire.

A guy tries to do a good job, and folks get suspicious. This is like the cop who gets suspicions when he sees someone actually obeying the speed limit, or -heaven forbid- actually stopping at a stop sign.