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Jon mackay
05-08-2007, 10:09 AM
Today I came accross a panel with a 30 amp breaker that was connected to a dryer outlet with a #6 wire. The dryer was on and the breaker was 15 degrees warmer than the other breakers and humming. Is this due to the over size wire?
Also during the inspection, the dryer stopped working but the breaker was not tripped, the home owner turned off the main breaker and turned it back on again and the dryer began to work again.

I couldn't figure out why, any thoughts?

Rick Cantrell
05-08-2007, 10:24 AM
Jon
The breaker may have tripped from being overloaded, or a weak breaker.
Check amps with an amprobe (dryer running on high), if it's not pulling to many amps (data plate on the dryer will give amps), suspect a weak breaker.

Jim Robinson
05-08-2007, 10:54 AM
They need to get an electrician out there. The homeowner shouldn't be tripping the main breaker to get the dryer to start back up. Something weird is going on. It's going beyond a normal home inspection, but were you able to tell if there was current through the dryer breaker when the dryer stopped, or had the main breaker actually tripped and was in need of a reset.

Richard Moore
05-08-2007, 10:58 AM
Nothing at all wrong with oversized wires as long as the breaker lugs are rated for them. Not allowed to snip strands off to make them fit as in your photo. But...that shouldn't be the problem.

I'd suspect a bad breaker first (who makes "General Switch"?). Did it still hum after resetting? But, there also could be something loose or intermittent at the dryer (or the receptacle).

It sounds like the homeowner does this regularly? Anyway...there definately is a problem. It's beyond your "scope" to fully diagnose it. Report what happened and recommend investigation by a licensed electrician and repair by him or the Maytag guy depending on the source of the problem.

BTW...that's one ugly wiring job at the panel. I think it's safe to say that the cable exiting the side of the panel and disappearing behind the door casing is not an acceptable wiring method!

Jon mackay
05-08-2007, 11:13 AM
The home owner just walked up and turned the main off and on before I even realized what he was doing.
I am recommending further evaluation by electrician and also noting that the breaker is not reated for such a large wire.

Richard Rushing
05-08-2007, 11:54 AM
The home owner just walked up and turned the main off and on before I even realized what he was doing.
I am recommending further evaluation by electrician and also noting that the breaker is not reated for such a large wire.

John, I'm not sure how you could determine that without pulling the breaker and looking at the embossment on the side (for the rating)...

As as what the homeowner did, you can bet s/he has done that many times before.

Richard

Victor DaGraca
05-08-2007, 01:28 PM
Was that Aluminum wire?

Paul Kondzich
05-08-2007, 01:35 PM
Victor, the aluminum wire is fine because that was not a branch circuit.

Victor DaGraca
05-08-2007, 02:13 PM
OK........ now I'm totally confused.
If it isn't the SEC and it is a circuit for a dryer, how is it not "branch wiring?

A branch circuit is defined as that part of an electric circuit extending beyond the last circuit breaker or fuse. The branch circuits start at the breaker box and extend to the electrical devices connected to the service. Branch circuits are the last part of the circuit supplying electrical devices. These circuits are classified in two different ways, according to the type of loads they serve or according to their current-carrying capacity.

Individual Branch Circuit
Installed in permanent locations such as an electric range, a clothes dryer, or an air conditioner. These circuits usually lead directly from the distribution panel to the appliance and do not serve any other electrical devices. These circuits can be any amperage size.

Tim Moreira
05-08-2007, 02:26 PM
I'm as confused as Victor.

Looks like aluminum wire to me. Also looks like some strands were snipped as Richard M. stated.

Last I checked, dryer circuits were part of the branch wiring.

:confused:

Jon mackay
05-08-2007, 03:34 PM
Yes, the wiring is aluminum #6.
The wire strands have been cut to fit the breaker.

So, it should technically be removed and replaced with a #10 copper wire??

Bob Mayer
05-08-2007, 04:21 PM
Yes, the wiring is aluminum #6.
The wire strands have been cut to fit the breaker.

So, it should technically be removed and replaced with a #10 copper wire??

The wire strands, as has been said, should not be cut. As RR said the maximum size of wire for the breaker ought to be stated on the breaker. If it will take 6 AWG fine - cut off the damaged end, but probably (not for sure), if it did fit, the strands would not have been cut. On the breaker it says it is for Cu/Al wire so one would think that it would take 8 AWG wire. So 8 AWG aluminum or 10 AWG copper could be pigtailed to the 6 AWG aluminum with the proper connector and the pigtail connected to the breaker.

- BOB

Victor DaGraca
05-08-2007, 04:36 PM
From the 2006 IRC:


E3306.2 Conductor material. Conductors used to conduct
current shall be of copper except as otherwise provided in
Chapters 33 through 42. Where the conductor material is not
specified, the material and the sizes given in these chapters
shall apply to copper conductors. Where other materials are used, the conductor sizes shall be changed accordingly.


E3306.8 Aluminum and copper connections. Terminals and splicing connectors shall be identified for the material of the conductors joined. Conductors of dissimilar metals shall not be
joined in a terminal or splicing connector where physical contact occurs between dissimilar conductors such as copper and aluminum, copper and copper-clad aluminum, or aluminum and copper-clad aluminum, except where the device is listed for the purpose and conditions of application. Materials such as inhibitors and compounds shall be suitable for the application and shall be of a type that will not adversely affect the conductors, installation or equipment.


TABLE E3605.5.3

The overcurrent protection rating for aluminum wire is as follows:
Copper amperage Aluminum
14 awg 15 amp 12 awg
12 awg 20 amp 10 awg
10 awg 30 amp 8 awg


E3306.9 Terminals. Connection of conductors to terminal
parts shall be made without damaging the conductors and shall be made by means of pressure connectors, including set-screw type, by means of splices to flexible leads, or for conductor sizes of 10 AWG and smaller, by means of wire binding screws or studs and nuts having upturned lugs or the equivalent. Terminals for more than one conductor and terminals for connecting aluminum conductors shall be identified for the application.

I think this covers it.:)

Jerry Peck
05-08-2007, 04:46 PM
The home owner just walked up and turned the main off and on before I even realized what he was doing.
I am recommending further evaluation by electrician and also noting that the breaker is not reated for such a large wire.

Sounds to me like the main tripped, and the homeowner is used to it, so he went and reset it - like he always does.

Not a good thing.

*Could* be just a bad main, they do go bad, anything 'just goes bad' sometimes.

*Could* be something is actually causing the main to trip, in which case the owner resetting it is only asking 'okay, something catch fire so I know where to start looking, come-on, catch fire now, I'm tired of having to reset this breaker all the time'.

Chris Ethridge
05-08-2007, 05:05 PM
that wire is sniped back way to much tell them not to run the dryer if they like their house

Eric Barker
05-08-2007, 05:52 PM
I must have missed something. Jon's post said nothing about a tripped breaker. As for the cut strands and warm breaker. The conductors has been derated - their capacity now in question. The few strands that are conducting current may have heated up due to the flow that they were carrying.

Jerry Peck
05-08-2007, 05:59 PM
I must have missed something. Jon's post said nothing about a tripped breaker.

You did not miss anything, that was my guess as to "why" the homeowner "knew what to do" to solve the problem.

If the dryer breaker did not trip (nothing was said about it tripping off and being reset) and the dryer lost power, and got power back just be turning the main off and back on (which is, by the way, how you reset a breaker), then my guess is that the main "tripped".

And that the homeowner automatically got up and 'reset it'.

'Because it trips so often.', again, my guess as to what would explain the homeowners actions.

Jon mackay
05-09-2007, 05:12 AM
The dryer had turned off, the dryer breaker did not trip but I do not recall if the whole house lost power. The bedroom light did not work but then I noticed a tripped breaker at the bottom left of the panel (you can see it in the picture).
I wonder if that was the problem (the main breaker tripping). Your comments are very helpful and I thank you.

I may contact the home owner and recommend he call an electrician.

Eric Barker
05-09-2007, 06:41 AM
Jon -

A better idea - call the client with electrician recommendation. Let him make the request of the seller. Then send a little backup letter for the record.