ProSoundWeb Community

Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => AC Power and Grounding => Topic started by: Jonathan Johnson on December 30, 2013, 02:58:46 PM

Title: Gotcha! Circuit breaker type codes
Post by: Jonathan Johnson on December 30, 2013, 02:58:46 PM
The following applies to North America.

If you are having your electrician  ;) install a new circuit, make sure that any breakers added to the electrical panel are of the brand and type code specified on the panel manufacturer's label. There are many brands and types that are nearly identical, and appear to be interchangeable. However, installing a Cutler-Hammer type BR in a Siemens panel that specifies type QP will be in violation of the National Electrical Code, and may fail inspection -- even though it will fit and probably won't be a problem.

Should a fire or other electrical problem result on a circuit, and it's discovered that a breaker of the wrong type code has been installed, it could result in denial of insurance coverage, a storm or lawsuits, or other unforeseen consequence -- whether or not the breaker is at fault.

The basis for this is that the manufacturers have not tested or certified other manufacturers' breakers for use in their panels, and neither has Underwriters' Laboratories. There are "universal" breakers available, but they are certified only by the breaker manufacturer, not the panel manufacturers. You may have similar liability issues using universal breakers as you would using an unlisted brand/type.

Also, most panels are "Class CTL" -- Circuit Total Limiting -- which limits the number of circuit breakers in an individual panel to 40 or 42. In order to comply with this, the panels are designed so that some spaces/stabs will accept only full-width breakers, while other spaces will accept full-width or tandem half-width breakers. (Some smaller panels will accept tandems on all spaces; some larger panels will only accept full-width.) There are tandem half-width breakers available which will install in the "full-width only" spaces, but these are only certified for use as direct replacements.
Title: Re: Gotcha! Circuit breaker type codes
Post by: Mike Sokol on December 30, 2013, 03:21:54 PM
Should a fire or other electrical problem result on a circuit, and it's discovered that a breaker of the wrong type code has been installed, it could result in denial of insurance coverage, a storm or lawsuits, or other unforeseen consequence -- whether or not the breaker is at fault.

Shakespeare: "The first thing we do, let's kill all the lawyers'' -- Henry VI, Part II, act IV  ;)
Title: Re: Gotcha! Circuit breaker type codes
Post by: John Roberts {JR} on December 30, 2013, 03:39:50 PM
I should not have an opinion about this, but it seems if the replacement breakers are also UL listed (presumably tested and safe). This seems a pure liability issue when the panel maker and breaker maker do the finger pointing dance to avoid blame. If the breaker depends that much on the specific panel for heat dissipation or some other subtle factor, it seems that too could be quantified.

This seems like a rule unusually favorable to the panel manufacturer?  I guess a breaker manufacturer could re-qualify the brand X panel with brand Y breakers at UL, but that probably gets prohibitively expensive if there are multiple brands of panels..

JR
Title: Re: Gotcha! Circuit breaker type codes
Post by: Jonathan Johnson on December 30, 2013, 05:11:12 PM
This seems a pure liability issue when the panel maker and breaker maker do the finger pointing dance to avoid blame.

When the finger pointing starts, make sure they don't point at you. (That's the point of my post.)

This seems like a rule unusually favorable to the panel manufacturer?

Of course. And let's say Eaton (the owner of the Cutler-Hammer brand) certifies Siemens QP breakers for use in their panels. Now Siemens redesigns the breaker, retaining the QP type code. Is Eaton's certification still valid?

Like I said, there is probably no practical difference between the breakers and panels, and interchangeability shouldn't be a problem. If you mix & match and there's a failure, it's likely the failure would have occurred if everything matched. Like you said, it's a finger-pointing blame-game between manufacturers, and if you mix & match that finger will eventually point at you.
Title: Re: Gotcha! Circuit breaker type codes
Post by: John Roberts {JR} on December 30, 2013, 05:37:48 PM
I am getting outside my wheelhouse but UL tests and lists safety critical components. If the manufacturer changes a component in such a way that it changes it's behavior they would have to retest with UL or give it a different unlisted part number.

Interchangeability of similar parts is not a new concept for manufacturing and safe as long as all of the parts are tested and listed as safe and equivalent for the application.

There may be something subtle about power panels that I don't understand, or this is as protectionist as it appears. I can see that the type breaker is restricted but the same brand requirement smells a little funny.

JR
Title: Re: Gotcha! Circuit breaker type codes
Post by: Stephen Swaffer on December 30, 2013, 05:56:15 PM
The manufacturers really need to come up with a NEMA standard for breakers, lawyers already have plenty of work!  Our local supplier sells Midwest meter bases with disconnects-by Siemens so presumably you should use Siemens branch breakers in them-but the supplier doesn't stock Siemens so guess how many get Siemens installed in them?  I recently installed a 125 A 2 pole breaker in one-the first brand I purchased cost double brand B.  Turns out, brand A (hi $) was defective, so I installed brand B.  Given that it is primarily a disconnect on a yard pole, there is little risk of serious trouble, still a frustrating situation.  I have yet to have an inspection failed for breaker brand-but then I try to play nice with the inspectors so they aren't  looking to make my life difficult!

If you have an electrician install a panel, it might be a good idea to make sure it is a well known name so that you can buy the correct breakers in 5 or 10 years.  I m quoting a job now that, due to a chimney fire, we have to rewire the living room.  That will require AFCI, and the panel manufacturer so longer exists-so either an AFCI oulet to feed the LR (kind of an ugly solution) or a new panel.  Because old panel install does not meet code, need a disconnect outside-basically a snowball effect that might be pretty costly for the home owner-much more costly than an extra 20% for a more well known panel a few years ago.   
Title: Re: Gotcha! Circuit breaker type codes
Post by: Jonathan Johnson on January 02, 2014, 04:45:42 PM
There may be something subtle about power panels that I don't understand, or this is as protectionist as it appears. I can see that the type breaker is restricted but the same brand requirement smells a little funny.

Really, the "same brand" isn't a requirement, as there should be nothing wrong with putting a Siemens-built type BR (if they made such a thing) in a Cutler-Hammer panel as the type designation would match the panel's labeling. Practically speaking, without a NEMA standard, the manufacturers don't have much economic incentive to cross-reference the types and could open themselves up to contrived liability by doing so. If there was a NEMA standard for breakers, it would remove a lot of that liability. It would also reduce the cost of breakers (and one wonders if it would reduce the quality) as manufacturers would not have an effective monopoly based on the need to buy breakers from the manufacturer of the panel.

It would be as if Edison sold light bulbs and sockets with a "medium" base and Westinghouse sold them with a physically identical configuration but called it a "standard" base. And Edison's sockets said "only use medium base" and Westinghouse's said "only use standard base." Using one in the other would be a violation of labeling and some inspector, lawyer, or opportunistic plaintiff would get their nose in a wrinkle over it and sue the pants off of the one with the deepest pockets -- and everyone would pay more for light bulbs.
Title: Re: Gotcha! Circuit breaker type codes
Post by: Lyle Williams on January 02, 2014, 08:21:46 PM
Philosophically, a standard is introduced to shift from "competition for a solution" to "competition for the selected solution".

The introduction of a standard drives cost and variability up.  The introduction of a standard does however stifle innovation.

Does the CB market need innovation?  Hell no.  We're 40 years past that.
Title: Re: Gotcha! Circuit breaker type codes
Post by: Jonathan Johnson on January 02, 2014, 09:36:26 PM
Does the CB market need innovation?  Hell no.  We're 40 years past that.

Most people under 30 probably don't know what a CB is. Corn Bread? Cheese Balls? Why would we need innovation in Cheese Balls?

Packet radio over CB might be innovation, but I'm not sure the FCC allows that. I'm not sure the FCC allows anything on CB besides voice chatter, but then again I haven't grokked the regs. Seems to me that music is or was prohibited.

EDIT: I now see you meant Circuit Breaker, not Citizens' Band radio. Was wondering why the topic swerve. Epic fail.  :-[
Title: Re: Gotcha! Circuit breaker type codes
Post by: Tim McCulloch on January 02, 2014, 10:49:20 PM
Most people under 30 probably don't know what a CB is. Corn Bread? Cheese Balls? Why would we need innovation in Cheese Balls?

Packet radio over CB might be innovation, but I'm not sure the FCC allows that. I'm not sure the FCC allows anything on CB besides voice chatter, but then again I haven't grokked the regs. Seems to me that music is or was prohibited.

EDIT: I now see you meant Circuit Breaker, not Citizens' Band radio. Was wondering why the topic swerve. Epic fail.  :-[

"Callin' all trucks, this here's the Duck, we're about to go huntin' bear."
Title: Re: Gotcha! Circuit breaker type codes
Post by: TonyWilliams on January 02, 2014, 11:22:18 PM

Epic fail.  :-[

I thought the same thing! Those radios haven't changed much at all over the years.


- Tony Williams
Title: Re: Gotcha! Circuit breaker type codes
Post by: Lyle Williams on January 03, 2014, 12:02:17 AM
:-)

A swerve from breakers to radio would have been a pretty big jump.
Title: Re: Gotcha! Circuit breaker type codes
Post by: Mark Cadwallader on January 03, 2014, 12:14:37 AM
:-)

A swerve from breakers to radio would have been a pretty big jump.

From what I recall of the '70's, "breaker" was a standard part of many CB transmissions.  [ KJKA 9970 ](IIRC).  Mark C.
Title: Re: Gotcha! Circuit breaker type codes
Post by: John Roberts {JR} on January 03, 2014, 12:28:32 AM
10-4 rubber ducky, catch you on the back side.

JR
Title: Re: Gotcha! Circuit breaker type codes
Post by: Jeff Bankston on January 03, 2014, 05:35:26 AM
i have a Texas Star DX 667. it swings to 749 watts on the technicians expenses(expensive) meter.
Title: Re: Gotcha! Circuit breaker type codes
Post by: Jeff Bankston on January 03, 2014, 05:45:06 AM
make sure the "interupting" rating is the same on all breakers. if they are 10,000 only replace with a 10,000 amp rating. if its 20,000 replace with a 20,000 , etc. if you want to find out more about this look up circut breaker interupting rating on the web.
Title: Re: Gotcha! Circuit breaker type codes
Post by: Mike Sokol on January 03, 2014, 07:53:08 AM
Cheese Balls? Why would we need innovation in Cheese Balls?

Cheeeeeeezzzzzzzeeeeee Baaaaaaaalllllllsssss. Yuuuuuuuummmmmmm!!!!!!!!!!! 

;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D
Title: Re: Gotcha! Circuit breaker type codes
Post by: Jerome Malsack on January 03, 2014, 09:28:27 AM
If you visit a good cheese factory and try the curds they will squeek when you bight into them. 

We get some each year we visit Wisconsin for our family get togethers. 
Title: Re: Gotcha! Circuit breaker type codes
Post by: Chris Hindle on January 03, 2014, 01:08:08 PM
From what I recall of the '70's, "breaker" was a standard part of many CB transmissions.  [ KJKA 9970 ](IIRC).  Mark C.
XM52-2384 or XNZ-45 on "our" private chanel. Halicrafters 8 freq. something-or-other, on crystals, in the basement.(Canada)
Yes, I'm that old. I remember Dad calling the airport for the height restriction, then putting up a mast that was 6" shorter. Any higher, and we needed a beacon on top. We were about 5 miles from Dorval Airport. This was around 1964, before "it" got popular.
With the second antena on the car, we got asked plenty if dad was a cop, or fireman. He wasn't.
Chris, and the swerve goes on.............
Pretty sure he meant CB as in Circuit Breaker.
Title: Re: Gotcha! Circuit breaker type codes
Post by: Mike Sokol on January 03, 2014, 02:00:46 PM
Chris, and the swerve goes on.............
Pretty sure he meant CB as in Circuit Breaker.

And after a VERY BIG swerve, we're back on topic. Sort of...  :o
Title: Re: Gotcha! Circuit breaker type codes
Post by: Mac Kerr on January 03, 2014, 02:40:53 PM
And after a VERY BIG swerve, we're back on topic. Sort of...  :o

That's a big 10-4 good buddy.

Mac
Title: Re: Gotcha! Circuit breaker type codes
Post by: Jonathan Johnson on January 03, 2014, 04:03:07 PM
Philosophically, a standard is introduced to shift from "competition for a solution" to "competition for the selected solution".

The nice thing about standards is that there are so many to choose from.  :o
Title: Re: Gotcha! Circuit breaker type codes
Post by: Jeff Carter on January 03, 2014, 09:17:53 PM
The nice thing about standards is that there are so many to choose from.  :o
Obligatory xkcd:

(http://imgs.xkcd.com/comics/standards.png)

http://xkcd.com/927/ (http://xkcd.com/927/)