Results 1 to 28 of 28
Thread: Double taps
-
07-30-2008, 02:30 PM #1
Double taps
Is this configuration acceptable in any form? Handy man states that feeders supply same applinance IE heat.
Similar Threads:Last edited by Chip O'Brian; 07-30-2008 at 02:37 PM.
-
07-30-2008, 02:39 PM #2
-
07-30-2008, 02:48 PM #3
Re: Double taps
No, this is not acceptable in any way because the terminal lugs are designed to properly secure only one conductor. This configuration does not allow for both conductors to make the proper contact with the lugs. I also don't see any anti-oxidant on the aluminum conductors, which must be applied when conductors are installed in the breakers for protection of the conductor.
Why don't they just move the double tap to the open breaker above as long as it is CU AL rated.
-
07-30-2008, 03:01 PM #4
Re: Double taps
Department of Redundancy Department
Supreme Emperor of Hyperbole
http://www.FullCircleInspect.com/
-
07-30-2008, 03:07 PM #5
-
07-30-2008, 03:07 PM #6
Re: Double taps
Why don't they just move the double tap to the open breaker above as long as it is CU AL rated.[/QUOTE]
According to the retired electrician/handy man can not split parallel feeders into seperate breakers.
-
07-30-2008, 03:36 PM #7
Re: Double taps
Hi Gunnar,
I didn't intend to imply that the aluminum condutors are a problem just because they are aluminum. The two aluminum conductors are being held together by the screw lug of the breaker (essentially a splice).
I would be concerned that this connection could work itself loose faster than copper.
It is not required to use anti-ox paste although it is good practice.
Sincerely,
Corey
Last edited by Corey Friedman; 07-30-2008 at 05:15 PM. Reason: spelling
-
07-30-2008, 05:07 PM #8
Re: Double taps
Corey (of course) addressed the main problem - parallel conductors, which Chip so stated.
From the 2008 NEC. (underlining is mine)
- 310.4 Conductors in Parallel.
- - (A) General. Aluminum, copper-clad aluminum, or copper conductors of size 1/0 AWG and larger, comprising each phase, polarity, neutral, or grounded circuit conductor shall be permitted to be connected in parallel (electrically joined at both ends).
(Jerry's note: There are some exceptions and some additional sections to this, however none of them apply here.)
Since those are obviously NOT 1/0 and larger, they are not allowed, *even if* the terminals on the breaker allowed for 2 conductors.
-
07-30-2008, 06:02 PM #9
Re: Double taps
Department of Redundancy Department
Supreme Emperor of Hyperbole
http://www.FullCircleInspect.com/
-
08-01-2008, 05:43 AM #10
Re: Double taps
From observing your picture this tap looks incorrect because the NEC does not permit conductors under 1/0 in size to be installed in parallel (310.4) these looks smaller than 1/0 and the lugs on the breaker may not be suitable for more the one conductor (need to check manufacture spects)
-
08-01-2008, 07:08 AM #11
Re: Double taps
Handy man needs to keep his paws out of service panels. Handy man needs to buy Home Depot Wiring 1-2-3 book and read. Handy man needs keep his paws out of service panels.
With the size of those conductors, there is also a good possibility some of the strands on the cables needed to be trimmed in order to cram everything under those contact screws.
Handy man bad!!!!
-
08-02-2008, 06:28 PM #12
Re: Double taps
Chris My question is: What is the actual condutor size (shown) and is sizing correct for the appliance(s) served. Is that a 60amp Breaker? How does one report this situation? chris
-
08-02-2008, 06:56 PM #13
Re: Double taps
Handy man = Mr. knowitall. Was he wearing overalls? My response would mostly mirror Nick's.
Beyond that, it makes me suspicious that the other/another breaker wasn't used when it is available.
-
08-03-2008, 07:42 AM #14
Re: Double taps
Chip: I am noticing this morning that the panel-box is recessed in a wood frame.No? and that is let into a brick cavity? How do the conductors exit? Where are the knock-outs located. Is a larger picture available? Would help me if you have one. How is the breaker notated on the cover?
Chris Bittner
-
08-04-2008, 07:54 AM #15
Re: Double taps
I know of breakers that accept two wires,but how can you recognize one when you see it? I saw this the other day. The two on top look like they were made for two wires and the one on the bottom is not. Am I correct?
-
08-04-2008, 07:58 AM #16
Re: Double taps
-
08-04-2008, 08:09 AM #17
Re: Double taps
Thanks Jerry. So if I see the breakers like the ones on top,then I can be confident in not calling it wrong. I'd hate to call out a panel with a double tap only to have an electrician pull the panel, take a quick look, say it's ok, put the panel back,and charge my client $50 for the visit.
Last edited by David OKeefe; 08-04-2008 at 08:29 AM.
-
08-04-2008, 08:41 AM #18
Re: Double taps
"then I can be confident" - that is a good way to put it, as the only way to know for sure would be to pull the breakers.
By the way, those breakers on top are actually not multiple tapped. Each side of that plate under the screw is its own "terminal". Either side, or both, may be used.
There area also some Cutler Hammer breakers which are rated similarly, although they are not as readily apparent, you would need to remove the breakers and read what is molded into the side of the case.
-
08-04-2008, 11:23 AM #19
Re: Double taps
How does one know (without pulling the breaker) whether it can accept a double tap or not?
Also does anyone have a good, easy to understand book they can recommend about electrical theory? Im looking for something that is not too technical but can teach in laymans terms about electricity. Why it seeks ground, how it seeks ground, conductivity, bonding, neutrals, etc
I basically know what to look for in a panel...whether its bonded, look for double taps, burned insulation, loose connections etc. I just want to learn in more detail on why.
-
08-07-2008, 01:00 PM #20
Re: Double taps
Square D makes a QO type breaker that will accept two conductors,other than that the double taps of the kind in both of those pictures should be repaired ASAP.
-
08-08-2008, 05:41 AM #21
Re: Double taps
Brian,
A standard breaker has a screw that the wire wraps around or the wire is directly under the end of the screws.
A breaker set for double lugging has a plate under the screw with a channel at each side of the plate for the wires to be under.
Go to a big box or electrical supply store and look at this stuff now instead of waiting to find it in a home. You'll be glad you did.
Erby Crofutt, Georgetown, KY - Read my Blog here: Erby the Central Kentucky Home Inspector B4 U Close Home Inspections www.b4uclose.com www.kentuckyradon.com
Find on Facebook at: https://www.facebook.com/B4UCloseInspections
-
08-08-2008, 05:57 AM #22
Re: Double taps
Eugene,
The multiple taps in that photo are *not* the main problem. Multiple taps are easy to correct, a 'no brainer' easy correction.
The main problem in that photo is the parallel conductors.
The correction for the parallel conductors is running new circuit conductors, of the correct size, from that panel to the appliance. That's going to be the 'hard part', and, after doing so, the multiple tap issue goes away anyway.
-
08-08-2008, 11:22 AM #23
Re: Double taps
Why are parallel conductors OK on the larger sizes but not OK on the smaller ones? What's the reasoning behind that?
-
08-08-2008, 12:44 PM #24
Re: Double taps
My understanding is being too many conductors in a raceway (derating), the terminals rated for that use (lack thereof) and lack of 'need'.
When you put two conductors together (the hots and neutrals must be in the same raceway) you start out with (in the case of 240 volt only circuit as shown) 2 phase conductors with 1 conductor in each terminal. As soon as you go to parallel conductors (using that same scenario) you now have 4 phase conductors (means derating) and you need terminals rated for two conductors.
Also, with smaller conductors there is no 'need' for using parallel conductors, use the next size larger. No much difference in conduit fill, etc.
However, take larger conductors and with parallel conductors they will be run in parallel raceways, and there are terminals rated for that use, and terminals made with twin separate terminals for the two conductors.
While 'need' is (I am sure) at the bottom of the list of reasons why not to run smaller parallel conductors ... why run two 14-2 NM cables when you can run 1 10-2 NM cable?
With larger conductors, why run two big honkin' 900 kcmil conductors and the large conduit it would take for them when you can run 2 sets of 250 kcmil conductors in much 2 smaller conduit runs?
-
08-13-2008, 07:10 PM #25
Re: Double taps
Jerry,
That top pic looks like it could be two seperate appliance.Its a 60 amp breaker and the owner said it was for heat.Why not just add another breaker.The bottom pics look like they could be just lighting or outlet circuits.Not all breakers with the plate under the screw are rated for double lugging.
Gene
-
08-13-2008, 07:15 PM #26
Re: Double taps
-
08-13-2008, 07:21 PM #27
Re: Double taps
Jerry,
Got it,but if you were to make an educated guess?
-
08-13-2008, 07:29 PM #28
Re: Double taps
Knowing only what we know, doing anything to separate them *might* cause some unintended smoking of wiring or electrical components, motors, etc.
You do know the "smoke theory" of electricity, don't you?
'Electricity is really smoke.' 'Let the smoke out and it no longer works.' That's because 'You no longer have any electricity in there.'
Getting the smoke back in there so it will work again is pretty darn difficult.
Bookmarks