ECN Forum Forums Photo Discussion Forums Photos for General Discussion The Worst Breaker Design Ever?

This is a Zinsco RQ38, 30 Amp plug-in 2 pole circuit breaker. I believe the only reason this one lasted is because it powered a dryer receptacle in a home with a gas dryer, and was never used. It's 3/4" wide.
(It's got "IQ65" stamped in a small emblem on the side; possibly the designer's test score?)









How do you like it?
Do you have any other candidates for the honor?




[This message has been edited by electure (edited 09-08-2006).]

Are those 'speaker terminals' used on a breaker????

Indeed they are. And the performance is about what you'd expect from them, too.

Believe it or not, this horrible piece was available in 40 and 50 amp ratings too!!

I still have a few Zinscos in my junk box, along with the bus assemply for an old mini (I think 4 space) panel.

I plan on breaking the one I have open to see what condition the internals are in. When I do, I'll post the pics....

My vote would have to be FPE Stab-loks. Between the handles being too wide to take the cover off without turning some of them off by accident, they were prone to just falling out of the panel if you did take the cover off.

Ya shes a real fine instrument.(sarcastic)

My nomination is the Bulldog/Gould/ITE Pushmatic. They were prone to fail to the ON position. Many never survive more than 4-6 on/off cycles.

I nominate the ITE "Blueline" series.. they were chincy little breakers that just felt "weak" when you operated them, and the buss-breaker connections were tiny and had a tenancy to burn up..

A.D

GE Skinnies. They don't trip, and an electrician (Yes, an electrician) said, "If that main didn't fry that skinny breaker would've let your house burn."

Ian A.

Geeze, I'm no spark and I know that 2x 50A breakers in a single would (at load) put an unholy amount of heat through the breaker. How on earth could even CH or SD build something to work, let alone Zinsco?

Personal experience is a funny thing; that's why we are taught that personal experience has no relationship to what the actual reality may be.

Failure at the buss connection is a good example of this principle. While we all "know" that certain brands are "junk," compare that opinion with my experience over the past five years.
(Again, I am only referring to failures where the breaker connects to the buss).

I've encountered this failure in:
1- Sq D "QO" 100 amp 2-pole
1- Zinsco 50 amp 2-pole
2- GE snap-in 20 amp 1-pole

Complicating factors included:
- The Sq. D was often run slightly overloaded (say, 108-112 amps); and,

- The GE failures were from a panel where the maintenace guy "cleaned the buss bars" with a wire brush on his Dremel (!!!!).

Zinsco failures??? I've encountered too many to remember. With the buss and the breaker contacts not seeing eye to eye on their purpose, I've yanked and relocated at least 50 or so 15 & 20A twins, maybe 20 or so 30A, 40A & 50A twins, a 55A(!)full size, 17 - 90A 2 poles from 3 switchgear sections in a mobile home park (replaced the buss on that one as well, too many 100A mains to count(most turned into panel changeouts) 9 - 200A (I forget the type,looks kinda like a Bryant BJ2200 from the front) Zinsco has made me ALOT of $$$
Then there's the prehistoric ones with the fork tabs right off the load side of the meter people got really creative when they wanted another breaker shoved in those things, usually a bite out of the outside cover will be present where someone made screwdriver contact to the outside cover while on the unfused fork terminals and likely saw spots for a few hours afterwards

I never came across too may FPE buss failures suprisingly.. maybe about 10 so far (I think they were all on the skinnies 30A and up) Most FPE probs I remember were internally in the breaker.

Funny to notice no one brought up the POS Crouse Hinds and Challenger skinnies which you could pretty much make your own combination, you could supposedly place 2 separate thin breakers on the same stab if you had a right side and a left side contact combination.. I've replaced TONS of those with MP-T's and QP-T's over time.., suffering from poor stab contact and arcing into uselessness.

I fully agree on the GE THQP's being good for nothing besides target practice.. I've broken more of the cheezy small plastic piece on the bottom under the terminal than anything else I've also seen more than enough THQP's with "bubbling" on the side indicating a huge amout of heat buildup within the breaker itself.. More than enough that I wouldn't ever install a GE panel.

Bulldogs seem to seize up and fail to reset mostly from what I've seen.. Remembering that Pushmatic was (and is to this date AFAIK) the only resi bolt-on panel out there. therefore your contact with the buss was as good as you were at tightening the screws down (which I've snapped the heads off more than once always a good idea to shut the panel down and run a tap through the buss hole if possible) Pushmatic breakers in coastal cities seem to collect unbelievable amounts of sand through the bottom vent opening also...

Anything else, I've seen about 5 CH style panels lose their mains in a spectacular display of just how much fault current can be at a resi panel. 3 Wadsworth panels that were simply beyond their expiration date, maybe 10 Square D XO panels suffering from the same as above. a strange looking Frank Adam panel which I couldn't locate anything for and ended up replacing. Some multi-breakers from Trumbull, SQ D and CH, none of which failed to do anything but reset. Even a couple QO panels here and there with buss/breaker failures..

I'd get into the aftermarket (Connecticut Electric et al) replacement crap, but my hands are starting to cramp

I read somewhere where Connecticut Electric has bought the rights to Zinsco from T&B, if thats the case Zinsco has gone from bad to horrible.

I don't thnink FPR is inherently a bad design, just a bad build back in the day, or else they wouldn't be so popular in Canada. Yes, I understand the problems they used to have.

I have seen bolt on westinghouse I think breakers.

We were dicussing in chat why FPE in Canada (Federal-Pioneer) does not seem to have the problems that FPE has had here in the states, my only guess is better QC. What do you say?

That's because Canada has more stringent standards, and the breakers are afraid.

The GE(THQP)Skinnies! A wonderful Choice. You can cram ever so much into such a small space Look, There's still room for 3 more circuits! Matched with aluminum Romex, a combo that's hard to beat by anyone's standards
(These match up at the white blob on the load lug of the 1st 40A CB Down from the poor 100A main).







[This message has been edited by electure (edited 09-12-2006).]

i use the GE "skinnies" in my shop & have never had a problem.they trip on overload & with a dead short, usually my goof up.i think the best still are the square D "QO" line though.

I like the QO line myself... If I was doing my service over again it would definately be Square D "QO"... I have only seen one or two of them ever fail at the buss-breaker connection.
As for the "Canadian" version of the FPE breakers I have only seen one or two failures of the buss-breaker connection, and one of which was due to severe corrosion from being operated UNDER WATER ( Spa pack, bad setup, don't ask)
I have run across a few of the "narrow" ones that will occasionally want to fall out of the panel but thats rare. The only problem I have with them is they are extremely slow to trip ( they DO trip though at least the Canadian ones do). Found these to be ideal for circuits for things like large A/C's ,table saws, HID lighting and the like, as I have had such loads nuisance trip square-D and Siemens /ITE breakers in the past. Just wish FPE would trip quicker during short circuits, just to keep the shower of sparks to a minimum
A.D

If you'll check out the picture page on my website, under 200 amp service I have a picture of a toasted breaker in the service panel. Maybe someone else will recognise the brand.

Dave
www.TigerElectrical.com

Dave: Nice Dodge you have in the pic!!
Looks like a C/H ( Cutler Hammer) or as we call 'em at the shop "Constantly Hot"

A.D

An update:

As promised in my previous post, I have broken open one of those lovely Zinscrap twins to check out the internals. A few surprises:

1) The mechanism sprang apart as I was separating the cases so unfortunately I can't show the exact layout of the parts;
2) There appears to be a thermal element, but I can't discern any magnetic element for short circuit tripping....hmmmm..maybe that's why these junkers never seem to trip or respond rapidly to a short...;
3) The contacts are tiny, I've seen toggle switches with beefier contacts;
4) Internal clearances are pretty tight;

and the biggest surprise of all:

5) NO INTERNAL COMMON TRIP!! The little metal clip on the external handles is the only link for the two poles.

The one I had actually did have the tiny screw terminals instead of the speaker connectors though.

It also had signs of contact wear (on one pole only) but no heat damage, and the internal lube for the mechanism is still good (but looks and smells like common petroleum jelly or "Vaseline.")

I will send pics with captions as soon as possible, next few days are gonna be busy....

I vote Stablock into worst design due to loose connectionsin almost every panel touched since the original install. And trying to get a new FP100 main is upwards of $300 on a good day for a residential breaker. But Zinsco panels have the worst phase bussings. Tweaked too easily making burn spots on buss and breakers.

As far as Europe is concerned I'd vote for these!
Schrack HLS, the Austrian equivalent of the infamous Zinsco No-Trip breakers!


At least the ones in this panel refused to trip on dead shorts in 2 out of 3 cases until the 20A slow fuse ahead of the fast 10A breaker blew.

Mechanically they're extremely sturdy, with porcelaine bases. One was lacking the "Off" button though... pretty ugly if you had to turn it off fast.
That's 1960s stuff, one row is hots, the other is neutrals.

edited for size, and to put on ECN server

[This message has been edited by electure (edited 09-23-2006).]

The great Zinscos were even advertised on the inside cover of the Los Angeles City Code book!
from 1974:

Well I guess in that era of poor construction methods, "aluminum wire", and disco, the Zinsco didn't all seem that bad..
Hmmm 10,000AIC, Up from 5000 AIC...

They do not trip anyway, so what good is that value I think when they read in the code where " all breakers shall be of the "trip free" design", they kind of mis-interpreted it!

A.D

[This message has been edited by Rewired (edited 09-24-2006).]