Sub Panel for 240V Only in Residence

[jar546]

This panel is fed by FMC and feeds 3 240V circuits only.

Is there something about this installation that stands out to you as a violation?
I'd say this is an easy one.

 

[Paul Sweet]

The only thing I see is an open knockout on the right side, but I'm not an electrician. Is it a subpanel for electric heat strips in a nearby air handler?

 

[classicT]

Similarly, not an electrical inspector... but there is (3) circuits and only (1) ground wire.

 

[Bryant]

Parallel conductors? should not the neutral conductor be marked with white tape?

 

[jar546]

Parallel conductors? should not the neutral conductor be marked with white tape?

There is no neutral in this panel.

 

[jar546]

Similarly, not an electrical inspector... but there is (3) circuits and only (1) ground wire.

There is one feeder coming into the panel with a ground and another single conduit leaving the panel with 3 circuits. The number of equipment grounding conductors is not a problem,

 

[jar546]

The only thing I see is an open knockout on the right side, but I'm not an electrician. Is it a subpanel for electric heat strips in a nearby air handler?

No sir, the 3 circuits feed a 27KW instant water heater

 

[Bryant]

There is no neutral in this panel.

So, if the neutral lugs are part of the grounding bar which is bonded to the grounding electrode system, then what is this conductor doing ? first impression is that the tape should be white indicating a neutral (grounded conductor), but I can't trace anything back to the equipment and only go on the assumption of what is being revealed.

When you said water heater it made me think about another setup whereas the two conductors hitting the neutral lug are actually hot conductors and the grounding (green tape) are neutral carrying conductors. As an example baseboard electrical heating elements whereas there are 2 conductors and a bare conductor, both the white and black conductors (romax) are actually two ungrounded conductors and the bare conductor acts as a neutral.
Is that what's going on here in this example?
Also how is a simultaneously disconnect achieved with 3 sets of 2 poled 40 amp breakers?
I also am not an electrical inspector, but am curious.
thanks

 

[jar546]

So, if the neutral lugs are part of the grounding bar which is bonded to the grounding electrode system, then what is this conductor doing ? first impression is that the tape should be white indicating a neutral (grounded conductor), but I can't trace anything back to the equipment and only go on the assumption of what is being revealed.

When you said water heater it made me think about another setup whereas the two conductors hitting the neutral lug are actually hot conductors and the grounding (green tape) are neutral carrying conductors. As an example baseboard electrical heating elements whereas there are 2 conductors and a bare conductor, both the white and black conductors (romax) are actually two ungrounded conductors and the bare conductor acts as a neutral.
Is that what's going on here in this example?
Also how is a simultaneously disconnect achieved with 3 sets of 2 poled 40 amp breakers?
I also am not an electrical inspector, but am curious.
thanks

Well, let me break this down. There is no neutral because there are only 240V loads. There is no requirement to turn off all 3 circuits at the same time. No white tape is needed because there is no neutral and none of the circuits require a neutral. Also with the smaller size of the wire, white tape would have been non-compliant anyway as the smaller size wire requires full length white insulation.

The problem that no on sees is the fact that they are using the neutral bar as a point of connection for the equipment grounding conductors (EGCs) and the neutral bar is not bonded to the panel, therefore a violation. FMC is the conduit used to feed this panel which is not good above 20A for an EGC so essentially the panel is not bonded.