3

PLEASE NOTE: UPDATED CIRCUIT NUMBERING FROM 12 & 14 to 14 & 16

I would greatly appreciate your help with trying to diagnose a problem that appears to be an open neutral. In my kitchen I have three circuits (C). They are numbers 14, 16, and 32 in my panel. C32 is a single GFCI circuit that powers only my microwave. When I use the microwave the voltage on C16 drops several volts from 120 to around 116. If I use another high current appliance (electric kettle) on C16 the V drops to 114-112. Add something else and it's dropped below 110V. I've pulled the receptacles and checked the connections and also used the little plug in tester and it shows they are all wired correctly.

Each of these three circuits also run through a manually switched Reliance generator panel. Today the power went out and I started the generator and switched the Reliance panel to the generator. I checked the voltage on C16 and it was 122V. I then turned on the microwave and the voltage on C16 started rising to 130V. In place of the microwave I then let the Well Pump (240V) kick on. After it started the voltage on C16 remained at 122V (running on the generator).

The last thing I tried this evening (back on house power) was to run the microwave on C14. In this case the voltage on C16 rose a little from 120V to 122V. Given that the two breakers are adjacent to one another I'm guessing they are on opposite legs in the panel.

I did check every connection on the neutral bar, ground bar, and every breaker, as well as the main neutral wire (multi-stranded aluminum) in the panel.

The other issue of concern is that my electric bill is about double that of my neighbors. I do have 3 teenagers and electric hot water so that could be part of the problem. :)

A friend who pointed me to the neutral problem told me that I may have recourse with the power company if the neutral problem is on their side. We have been through several microwaves, etc. My outside feed is from a pole not underground.

I apologize for the long winded description but I'm hoping it shed some light as to where the problem may be.

My question is this:

How can I determine if the problem is on circuit side of the panel or the meter side? If I can determine it's on the meter side, I was advised to call an electrician to check the meter connections before calling the utility company as I don't know how apt they would be to take responsibility if it is on their side.

Here is a photograph of the circuit breaker panel:

Cutler Hammer Circuit Panel cover removed

Photo of Panel Label:

Cutler Hammer Panel Label Photo of Reliance ProTran Switch Model 31410CRK:

Reliance ProTran I have checked all the connections for the transfer switch and I have added a tie bar to switch both legs of a MWBC between B-G on the transfer switch which are circuits 6 and 8 in the panel. Otherwise everything is exactly as specified.

20
  • 1
    I would start with a call to the power company - you may find them more accommodating about checking this out than you appear to be assuming. – Ecnerwal Jul 30 '16 at 3:39
  • 2
    What type of panel do you have? Better yet, can you provide us with photos of it? – ThreePhaseEel Jul 30 '16 at 3:43
  • 1
    Also, can you provide a photo of the panel's label? (It should be on the inside of the door) – ThreePhaseEel Jul 30 '16 at 15:02
  • 1
    I like my CH panels. However you must have the space numbers wrong. CH numbers left to right top to bottom. Space 12 is the bottom half of DRYER 1. Anyway if these breakers are adjacent, they are on opposite poles, which suggests to me they may be a multi-wire branch circuit or MWBC. These share a neutral, so the neutral problem could be local to the MWBC. The way to tell is check other unrelated circuits for hot-neutral voltage changes. – Harper - Reinstate Monica Jul 30 '16 at 22:19
  • 1
    @Harper The bottom conduit goes to a Reliance #31410 CRK Manual Transfer Switch for Portable Generators. The Switch is prewired through the conduit. It comes as a complete setup. There is only one neutral which had me wondering. There may be an issue with load balancing but when it is switched to generator they are all done at the same time. – Eric Mark Jul 31 '16 at 0:49
1

Both your circuits' hots are red wires... Ok... But I follow them, and several pairs of wires are cable-tied together which suggests 240V or MWBCs, ok..., and they both disappear into the bottom conduit, where--

What, the, actual, heck...???

-- there's like 20 red and black wires going into this fat conduit, And Only One Neutral!

You can't do that!!! A bajillion circuits can't share a neutral! Each hot gets its own neutral, except for MWBCs where two hots share 1 neutral. You can't have a MMMMMMMMWBC!

You also can't put more than 9 wires in a conduit without derating (using thicker wire).

This is either a total nightmare, or needs some serious explaining. Who did this work?

12
  • The bottom conduit goes to a Reliance ProTran #31410 CRK Manual Transfer Switch for portable generators. It's prewired that way. – Eric Mark Jul 31 '16 at 0:34
  • 1
    WTF? Reliance is responsible for that nightmare? sigh – ThreePhaseEel Jul 31 '16 at 0:55
  • @ThreePhaseEel Is this a design issue or an install problem? I'll admit to doing the install but it was per the manual. Unless I've messed up by including only part of an MWBC? – Eric Mark Jul 31 '16 at 1:03
  • 1
    Guys!! Calm down!.... Those transfer panels are completely legal and very common. I've installed dozens myself. ...... The neutral is only for the receptacle and/or meters on the transfer panel. The circuits still original in the main panel and that is where their neutrals are terminated. The transfer panel switches are just wired thru the DPST switches, choosing either the breaker or push-button breaker on the transfer panel. – Speedy Petey Jul 31 '16 at 23:05
  • 1
    Also, the flex is under 24" so derating is a non-issue. – Speedy Petey Jul 31 '16 at 23:07

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.