How is this circuit working?

[Rob Colecchi]

I came across an unusual circuit the other day and just wondering if anyone would know what it would do to the outlets/lighting fixtures. The house is in foreclosure with a ton of homeowners specials. This issue is in the main panel, I showed it to the client, explained why it was wrong and wrote it up for further evaluation etc… However just for my own knowledge I want to know what it going on with the circuit or even how it is actually working. Background info: 100 Amp/240 Volts breaker panel, conduit system, no labels in the box. The issue: One 15Amp single pole circuit breaker on the left side of the panel board with a 14 gage conductor attached (via a wire nut) to another 15Amp single pole breaker on the right side of the panel board. Theses two conductors have a third 14 gage conductor on the same wire nut (three wires tied together) this one conductor leaves the panel. The purple wires in the pix are the feeds from the circuit’s breakers and the gray wire is the conductor leaving the panel. The return path (neutral and ground) is a 14/2 romex wire which lands on the neutral bus. Due to drywall and the lack of labels I can not tell what the circuit is feeding (I think it is to the detached garage). I did not think to look until I was on my way home but I do not know if the two breakers are on the same SE line or on SE separate lines. My outlet tester did not find anything ususal with the outlets in house or garage. Here are my questions: 1. How is this circuit actually working? 2. What does this due to the outlets and lighting fixtures? 3. If they are on the same SE line this can’t be a 30 Amp circuit can it? 4. With a conduit system the ground should be via the conduit however with a romex wire installed is the neutral and ground wire just like bonding the neutral in sub-panel? 5. Is this circuit back-feeding the SE lines? Any input would be great.

[Richard Moore]

I’ll take a stab…but it is dependant on your description being correct.

1: The two breakers must be on the same leg (phase), otherwise one of the breakers would have tripped (or the wires melted).
2: Assuming #1 is right, nothing. You still have a 120 volt circuit.
3: Again assuming #1, then yes, two breakers used in parallel like that will split the load…fairly evenly. You effectively have a 30-amp breaker protecting #14 wires. Not good! Actually, the only reason I can think of for someone to do this is because they were overloading and tripping the 15-amp breaker in the first place. This was their...ummm..."fix". FYI, if the circuit got to, or close to, 30-amps then one breaker would trip followed immediately by the other. Of course, you may have a fire started by that time!
4: If you have 14-2 plus ground inside metallic conduit, I think you should use the “romex” grounding wire, just because it is present and not doing so could lead to confusion. (but either would work)
5: See #1. In other words…no.

BTW...got a photo of the whole panel?

[Rob Colecchi]

Richard,

Thanks for the reply, your answers make sense.

[Randy Aldering]

Any chance this could be for a whole-house surge suppressor?

[Jerry Peck]

Any chance this could be for a whole-house surge suppressor?


The issue: One 15Amp single pole circuit breaker on the left side of the panel board with a 14 gage conductor attached (via a wire nut) to another 15Amp single pole breaker on the right side of the panel board.

The above is why what Richard posted (below) makes sense.


1: The two breakers must be on the same leg (phase), otherwise one of the breakers would have tripped (or the wires melted).
2: Assuming #1 is right, nothing. You still have a 120 volt circuit.

And why it would not make sense for it to be a surge protector as both line leads would be on the same phase.