Split main breaker design in Pushmatic electrical panel (C) InspectApedia DB Bulldog & ITE Pushmatic Circuit Breaker Compatability & FAQs

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ITE / Siemens Bulldog Pushmatic Breaker FAQs:

Questions & answers about Pushmatic circuit breakers and panels.

This article also discusses the cross-compatability of Bulldog, Pushmatic & ITE Circuit Breaker compatability & compatability of replacement circuit breakers for these electrical panels. The article continues with reader FAQs about Bulldog & Pushmatic electrical panel & circuit breaker performance & reliability, including a split bus design and main breaker features in the panel.

The article series discusses the history of Pushmatic breakes, gives advice to homeowners whose building is served by a Pushmatic electrical panel, and we discuss both compatability of and concerns when using replacement circuit breakers or used Pushmatic circuit breakers sold by salvage operatoers.

We solicit field failure and field inspection reports of questionable or possibly problematic electrical equipment in buildings such as the Bulldog™ and ITE-Pushmatic® brands described here.

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Bulldog, Pushmatic, ITE-Pushmatic, Siemens Pushmatic Circuit Breaker FAQs

Bulldog pushmatic circuit breaker labeling (C) These Questions & Answers about Bulldog Pushmatic and other Pushmatic™ brand circuit breakers were posted originally at x, be sure to see that article.

On 2018-01-11 by (mod) - is a Bulldog Electric 20 amp, single pole push-matic breaker is SWD rated? Defintion of HID vs SWD rated circuit breakers.


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A short answer, with help from Dr. Jess Aronstein, is that if you do not see an SWD rating on the circuit breaker label you should assume that it is NOT SWD-rated.

Per UL 489, the switch-duty rating label (SWD) may be applied to one, two and three pole 15 A and 20 A circuit breakers, 347 Vac or less that pass the special SWD test requirements. The SWD rating applies to breakers used for regularly switching flourescent lights.

For other readers,

Circuit breakers used to switch 120V or 277V fluorescent lighting circuits must be listed and marked "SWD" or "HID". Circuit breakers used to switch high-intensity discharge lighting circuits must be listed and marked "HID".

UL 489 (Standard on Molded Case Circuit Breakers) permits "HID" breakers to be rated up to 50A, whereas an "SWD" breaker is rated up to 20A.

The tests for "HID"` breakers include an endurance test at 75 percent power factor, whereas "SWD" breakers are endurance-tested at 100 percent power factor.

The contacts and the spring of an "HID" breaker are heavier duty, to dissipate the increased heat from greater current flow during the HID ignition period.-
[Courtesy of Mike Holt newsletter 10/22/03] - excerpt from Schneider Electric - retrieved 2018/01/10

Dr. Jess Aronstein, is a research consultant and an electrical engineer in Schenectady, NY. Dr. Aronstein provides forensic engineering services and independent laboratory testing for various agencies. Dr. Aronstein has published widely on and has designed and conducted tests on aluminum wiring failures, Federal Pacific Stab-Lok electrical equipment, and numerous electrical products and hazards.

Contact: J. AronsteinConsulting Engineer Bme, Msme, Ph.d., N.y.s. P.e. Lic. No. 39860, 909 Londonderry Ct., Schenectady, NY 12309 USA, Tel: (845) 462-6452 Email:

On 2018-01-10 1 by Heather Scott

Could you tell me if a Bulldog Electric 20 amp, single pole push-matic breaker is SWD rated?

On 2015-12-04 by (mod) - where to get replacement Pushmatic circuit breakers?


There are companies selling replacement circuit breakers that fit into the panel. Why someone would want to do that, given the safety concerns raised above, is another question. The link discussing replacement breakers is given immediately below where you see the question you posted.


On 2015-12-04 by doralee

is bulldog electric still in business can you still get circuit breakers

On 2015-10-20 by

Are they still around can we buy them ? Have a box that takes them needs a double 30 amp,where would we buy them.

Compatibility of Bulldog, Pushmatic, ITE-Pushmatic, Siemens Pushmatic Circuit Breakers

Pushmatic electrical panel (C) Daniel Friedman Matt StegerReader Question: What's the difference between ITE Pushomatic and Bulldog Pushomatic and ITE Pushmatics?

Is there a difference between the ITE Pushomatic breakers and the Bulldog Pushomatics? I have not seen a "ITE Pushomatic" panel with the words "Bulldog" on them. - Peter Bennett


We agree that we need more precision on this point and the text on this question is deficient. We think it's a matter of history of ownership and name changes but an online search in January 2011 [and again in 2014] did not find solid information about compatibility nor variations in the performance of these push-type circuit breakers among different labels and ages.

In the home page for this topic, PUSHMATIC - BULLDOG PANELS,

and at BULLDOG PUSHMATIC DESIGN HISTORY you can see some of the patent history and product names of this circuit breaker design.

Comment: Bulldog Pushmatic, disassembled, examined, comments

I have recently dismantled a Bull Dog Pushmatic breaker. The Bull Dog breakers have both, a electromagnetic, and a thermal element. The electric coil is under the metal strip, and pushes up on it.

I suspect a design change was made in the breakers, sometime in the 50's and I'm not sure that some models were not electromagnetic only. I can recall from childhood that they trip instantly, with almost no spark. My father, an electrician, was messing with the xmas lights. I am a retired electrician. Getting them to trip at a lower amperage, and reassembling them is a bit of a nightmare. - Brian Torch - Canada


I too grew up with the view that Bulldog Pushmatic breakers were particularly nicely made and appeared to me to be of high quality. It was later after working as a field investigator and as an editor here at InspectAPedia that I was informed about concerns with the product performance. - D. Friedman, Editor.

Question: Phantom trips on 100A main Bulldog Pushmatic circuit breaker

I read your page on bulldog pushmatic breakers. I have a bulldog panel in my old home that was installed in an electrical system upgrade in the early 1960’s. It has worked fine up to about 2 years ago. Now we experience random “phantom” trips of the 100 amp main breaker.

No other circuits trip when this happens and it usually happens when there isn’t any significant loading of the system going on. It doesn’t feel hot and when reset, everything works fine for a month or two or three then it happens again. Could this be due to surges? Or is more likely to be just an age problem? I was told it might be cheaper to replace the whole panel with a newer one than to find a replacement main for this box. - J.W., Michigan


Because you are not aware of an overcurrent, that is, the main switch doesn't seem hot and you're not reporting visible arcing or odors, I'm still guessing that a breaker has an internal failure. I follow your suspicion that the problem is in the main switch.

But you could have a clandestine problem elsewhere in the electrical system or at one or more circuits fed from your Pushmatic panel. Circuit breakers are required to trip on a varying timeline depending on the level of overcurrent.

So a more modest overcurrent (say an overloaded branch circuit) that runs for a long time and that should have tripped an individual breaker could be passing on its problem to the main switch without generating as much obvious tactile heat.

You or an expert could monitor current draw at the mains and across in-use circuits to see what's going on, though from your description I'm afraid it might take a long time to track down.

So what's phantom? Power surges on active circuits or a more hidden problem in the building's wiring, circuit usage, or breakers in the panel.

I agree that it would be economical (and probably more reliable) to replace the panel and breakers all as a set.

If you take that step and if you are interested, CONTACTus and I can send you instructions on mailing in your equipment for an expert overcurrent test - there's no cost to you but the shipping. I bet that our associate David Carrier would be glad to put your equipment onto a test bench to see what's going on.

Question: One circuit breaker in my Bulldog Pushmatic panel keeps tripping.

I recently bought a home built in 1960 that has the Bulldog panel and Pushmatic breakers. One of the breakers is constantly tripping. I am almost 60 and leave alone. Should, in your opinion, I look for a replacement breaker or should the entire panel be switched out? From what I read on your website this old electrical panels don't seem to be very safe. Thank you. - C. 8/10/12


A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem in an electrical panel. For example in the case you describe, one breaker repeatedly tripping, it is possible that the circuit breaker is doing its job - and that there is an overload or short circuit or other defect on that particular circuit.

That said, you have read that there are trip problems with some of this equipment; the safest policy would be to replace the panel.

But I would first ask your licensed electrician to thoroughly check the circuit whose breaker keeps tripping. For example, in addition to testing the circuit and the items connected to it, s/he might try swapping that circuit over to a different breaker in the panel to see if the problem recurs. That might give you a breather while waiting for the panel replacement.

Reader Comments about Bulldog Pushmatic Field Experience via Comments Box, 2011 - 2013

Moved here to preserve text from outboard Comments Box system Jan 2014.

(Apr 20, 2011) Brian Torch  said:

We had Bull Dog Pushmatic breakers in the house when I was a kid. They would trip instantly if you shorted the circuit; with almost no spark! You could touch two hot wires and no spark, almost, it would trip that fast....

I have dismantled one, to try to reduce the amperage that it trips at, for use on a model railroad. Bull Dog Pushmatic breakers are magnetic, instant trip breakers. There is no thermal system inside; no hydraulic system. Devilishly confusing, and difficult to work on.

Of course, Instant trip sounds just great...but it can be a nuisance...Tripping all the time. Like when you load up a power tool.


(Oct 30, 2011) can  said:

The ITE, Gould and Siemens labeled Pushmatic breakers all have magnetic trip and thermal trip features by applying a magnetic coil in series with a trimetal. Magnetic trip time within 1 1/2 cylces at 60 cycles. Manufactured in Bellefontaine, Ohio and nolonger produced.

(Jan 28, 2012) Edward Rossi  said:

I worked for ITE Imperial (the company name seems incorrect above) from 1974 until 1978. I am certain that the Bulldog/ITE Pushmatic breakers sold at that time nd for many years prior did have a magnetic trip.

The was an old display that I found and used then which compared the tripping time for both overload and short circuit type faults between the Pushmatic device and others sold at the time. Under all normal circumstances, the Pushmatic breaker operated more quickly under short circuit than any competitive device. Based on the older sales engineers in the office at the time (and product literature) this was due to the "five turn coil" used in the magnetic portion of the tripping mechanism.

I sold literally thousands of these breakers for use on job site temporary power poles since the loadcenter could be much narrower (fitting on a pole easily), and because the Pushmatic breaker attached to the bus with a screw instead of the expected spring clip. This fact also led to the Pushmatic being used on projects where the specification was for bolt-on panels. There was -- for at least a short period -- even a three phase version manufactured.
For both the pole pole application, and when used in outdoor residential metering equipment (which was very common in Southern California), there were issues associated with dust entering the breaker and not allowing it to reset. Whether it was appropriate or not, the generally applied solution was to spray the breaker with WD-40.

Reply: thank you for the comment Mr. Rossi, I will add it to the articlde text.

(May 15, 2012) Joyce Cunliffe  said:

I have a panel box MAIN B1919PO1A. Can you tell me the age of this panel box?

(Aug 27, 2012) Tim  said:

The home inspector opened my electric box and said my house could burn down. I have an ITE Pushmatic panel, 150 Amps main breaker and about 20 others breakers. A couple have two wires under the screw where power comes out.

The bigger breakers have a different kind of screw for the wires. It looks like you push a the wire into a hole and tighten the little screw. The ones with two wires have a screw with a larger head and pad(?) where it looks like two wires can be fastened in place. the home ispector said this is illegal and against code and lead to fire.

It's been that way for 20 years. I have never had a breaker trip. Do you have an place I can find documentation to support the two wires under one screw? I need to show it to the buyer.

(Oct 20, 2012) Jan Gates  said:

Our home was built in the late 60's. There is a Bulldog Push-matic, Electri-Center panel. How do i find the total ampage. My insurance company wants to know. There are two switches that say 30amp on both sides, then there are 6 more that say 20.

(Dec 22, 2012) Rick  said:

Condo I own, built in the mid-1970's has aluminum wiring and ITE Pushmatic breaker box.
When the water heater cuts in, I can hear a buzzing sound from 30A circuit breaker (?) that feeds the water heater.
In addition, this breaker is difficult to reset if I use it to shut off hot water heating.

I'm thinking I should replace that 30A double pole breaker.
Good idea? Could this be a wire connection that has loosened due to aluminum wire?
Thanks In Advance.

(Jan 3, 2013) DAVE  said:

Im a licenced electrician i have put in many pushmatic panels i have also disected many breakers and the bulldog higher amp breakers were strictly magnetic but the lower ones were always thermal magnetic and would trip instantly on a short

they were probably the best breakers of the 50s then square d came out with there QO i use qo to day its the best .ive looked at the mains in qo panels from the early 60s 50s those were thermal also. I also stay away from the love that has aluminum bus bars ive seen countless failures.

(Jan 4, 2013) JACK DOUGLASS  said:

I would like to replace the pushmatic breaker for the "throw type" I can never tell which breaker it tripped as the flag stays in one position. Is there a replacement brand that you could suggest

Home Inspector Comments on Bulldog Pushmatic Breakers & Panels at Home Inspections

Split main breaker design in Pushmatic electrical panel (C) InspectApedia DBReader question: How Many Main Breakers are Allowed in a Residential Electrical Panel?

Reader Question: Recently I inspected a ITE Pushmatic main panel box. At the top of each buss line there was a main breaker. What is the current policy regarding this type of main panel box wiring configuration? Is there need for further evaluation by a licensed electrician? -D.B. 1/22/2014

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The short answer is that we are allowed up to two main switches to turn off power in the main electrical panel. A sub panel containing 6 circuits or less can omit a separate main breaker and may be switched by the breaker on its input feed circuit.

Details & example electrical code citations are provided where this question is discussed in more detail

But there are other issues with Pushmatics that argue for viewing this equipment with caution. I'm not confident that the advice "have the panel examined by an electrician" is at all an adequate warning, since there are surely electricians living by rigid code interpretation who will deem safe electrical panels known to have safety defects but that have not been subject to a government-ordered recall.

Clear examples are FPE Stab-Lok equipment, and two more possible examples are the Bulldog-Pushmatic panel and also Zinsco panels. Where we have independent, unbiased testing and field reports of comparatively high levels of field failures, an astute home inspector, electrical inspector, or electrician ought to call out those hazards - even where they may call for a costly panel replacement. (The last man in to touch the equipment will be blamed if/when there is a fire or catastrophe).

What constitutes "comparatively high levels" of failures. Professional inspectors, operating without conflict of interest (not profiting by repair work) and charged with client safety and building occupant safety are entitled to reasonably-founded opinions.

So when Aronstein reports that for residential circuit breakers the fail-to-trip rate is infinitesimally small, perhaps less than 1 in 100,000, and we have a 2-pole breaker that fails to trip 67 times in 100 cases, that's surely a "high level" failure rate. Take a look at the articles organized at PUSHMATIC - BULLDOG PANELS

We've had field reports of failures, including a dangerous condition of uncertainty about whether a circuit is switched on or off - in this equipment line. Some other home inspector opinions (Bell who asserts missing design components) that I also cite in that article are more uncertain as Mr. Bell has never responded to my requests for his data source and citations, and as his view is only partly supported by the patent data I located.

If I understand your photo, you are pointing (your dangerously close bare fingers made me nervous) to a pair of split-main breakers, an arrangement that lacks a common internal trip or external trip tie. This design would allow one side of the panel to be switched off while leaving the other side "on".

Reader follow-up:

[...] Regarding the photo showing my fingers dangerously close to the panel wiring; after looking at the photo posted on-line I can understand your concern. I have the utmost respect for the danger present inside any electrical panel box, and even though my fingers look as though they are almost touching panel wiring they are a healthy distance from the panel circuitry.

The angle the photo was taken from does make it look as though my fingers/hand are very close though, and it certainly doesn’t hurt to reinforce the warnings about the dangers of inspecting an electrical panel box.

The comment you made in your reply about some electricians…”since there are surely electricians living by rigid code interpretation who will deem safe electrical panels known to have safety defects but that have not been subject to a government-ordered recall…” was right on.

On this issue I also contacted a local electrician and explained to him what I had seen at this inspection. He did not have any problems with the duel main breakers, but he also did not have any issues with Pushmatic breakers. In fact, he praised Pushmatic breakers as being reliable. The information provided by you and other sources on-line indicate that there are serious questions about Pushmatic breakers, which should be included in any report to the client.

[...] and I will revisit these issues with this client. Your comments also prompted me to read other related issues on main panel boxes that were posted on your website. - D.B. 1/24/2014


[...] About the field and research involving Pushmatic circuit breakers, we have seen enough to justify a warning that there is a reasonable basis to treat the equipment as significantly more of a hazard than most (not all) other similar equipment.

In the 1980's before beginning to collect this information, the physical appearance of that equipment looked to me like a product that was in fact better-made than many cheaper, more flimsy-looking brands.

It was therefore a disappointment to learn that the "highly reliable trip rate" of these circuit breakers could for some users turn out to be a source of "nuisance tripping" - an error in the safe direction though one that can form a subtle hazard, while at the same time there was the very serious shock hazard of reset difficulties that could fool someone into thinking that power was "off" when it was "on".

Remarkably, the company's own employee's description of having to spray Pushmatic circuit breakers with WD40 to get the breakers to re-set is itself confirmation of a product hazard, and it also raises a worry about the technical depth of the person who made that statement.

WD40 is not only a light lubricant, it's a great solvent that would very nicely dissolve any grease or permanent lubricant that might be used inside some circuit breakers - leading to future failures.

A difficulty faced by any individual, association, or even government agency such as the US CPSC is that where money and liability are involved there are usually fellows who will argue and fight vigorously to protect from recall even the most hazardous product.

Un-published are court-sealed records about heinous cheating, bribery, and ugly risks to consumers for another circuit breaker brand, and un-published too is a lengthy harrassing and hectoring series of emails and demands I've received from a fellow who, although he refuses to honestly identify himself, has clearly got an interest in putting the cabash on information we've received and published about the Pushmatic product.

While ultimately we'd like to rely on the government or allied safety agencies to discover hazards, assure competent independent testing to investigate them, and to take appropriate warning or recall steps when appropriate, we cannot assume that that process always works as it should.

Indeed on occasion managers in such agencies have been so frustrated by the disparity between research results and money or threat-driven policy decisions that they've asked people like me who are independent publishers to demand and publish information under the FOIA where otherwise it would not have been released to the public.

About your finger near that Pushmatic breaker, I know you were smart enough not to electrocute yourself.

As a publisher/editor I have to worry about risks to a casual reader, a careless homeowner, or someone who just lacks respect for electricity. The chance that someone else will fail to understand that they need to be careful when inspecting electrical panels is a worry that leads me take opportunity to point out shock hazards where I can see them.

Even though at home inspections I habitually stood blocking my inspection client from direct access to the electrical panel as I examined that component, I once had a client reach right over my shoulder and stick his finger right into a live fuse socket while asking "What the heck is this!" The results were exciting.

And at a home inspection training seminar we had an electrician tell newbie home inspectors how to inspect the electrical panel by saying "Well the first thing you wanna do is grab a-holt of each of the entry main wires just above where they come into the main breaker - and give them a good shake!" I could just imagine that with that fool statement he had probably killed one or two of the fellows in the room, sending 240 volts right through their hearts.

[We] very much welcome contributions, questions, and critique concerning the topics you find or find missing at - working together makes us smarter than any individual. - DF


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