Zinsco circuit breaker problem

[mattwakeling]

I live in a 1960's condo in Souther California. Some of the circuit breakers have been buzzing since I moved in a few months ago. One in particular would lose power until it was manipulated into the right position on the breaker box (some of the breakers are very loose). A few days ago, the most problematic breaker stopped working, killed the fridge, and I have not been able to get power back to this side of the condo since.

The breaker of interest is a double 20amp 2-pole Type Q Zinsco R38. There does not to appear to be a main breaker that powers down everything in this box. Am I running any great risk by taking this breaker out while with the wires still hooked up to it (or even disconnecting the wires with the breaker switched off)? I am willing to face anything but death; I'm young and healthy, and I fix cars and computers and do some home repair (just fyi). My idea is to replace the breaker with another, less critical, breaker from the box just (i don't need all of the wall receptacles to have power).

I will appreciate any thoughts on this issue.

Thank you.

[RBM]

There is probably a main disconnect for your panel at the metering equipment, and it would certainly be the safe thing for you to do, to turn it off. It's entirely possible that the buss in the panel,(the electrically live metal parts) is damaged and this is why the breakers are not making solid contact. You would probably be wise to have an experienced person look at it, and replace it if necessary

[Speedy Jim]

Easy one.

GOOGLE: Zinsco problems

You are sitting on a well-recognized bomb.

Jim

[DanG]

Zinsco breakers are notorious for being bad and are not supported by anyone and they are not rated by UL.

Parts and pieces tend to be expensive. There were some replacement systems that removed the "guts" of the panel and replaced the bus and breakers.

Electricians can work hot breakers, but everyone would prefer killing the power. If you are not familiar with the work, get a licensed electrician involved. Be aware, all electricians will suggest replacing the system. Most will not have Zinsco breakers nor have much interest in finding them. ___________________________ Keep the whole world singing. . . . DanG

[marks542004]

It is relatively safe to work on a breaker with the breaker off.

I would switch off all breakers, remove the wires from the breakers involved , swap out the breaker thats faulty and then reconnect the wires.

The bus that feeds power to the breakers is not exposed with all breaker positions filled.

However, HOWEVER, it is much safer to cut power to the box . There is probably a disconnect on the main distribution and meter panel.

As others have suggested you might do better to have the box replaced.

You are only talking about an hours work if it is a straight box swap.

[Bud--]

A humming sound from breakers is pretty normal. A sizzling sound indicates an arc. Having to move the breaker to get to work sounds like a bad connection to the bus - arcing.

If you are moving the wires to another breaker you don't have to remove the bad breaker, just move the wires. Wires from multiple breakers can be pigtailed together and connected to a single breaker of the same amp rating. If the circuit has 2 hot wires sharing a single neutral you have to know how to do this safely. Kitchen and laundry cirucits shouldn't be combined.

If you remove the breaker and leave it out you will have an open space to the bus with the trim cover back on unless you have a filler plate - not safe. If the breaker arced to the bus, that bus position is damaged and a new breaker should not be installed there. On the otherhand, if there is major damage to the breaker it should be removed. If the breaker does not come out easily I would be real nervous about pulling a Zinsco breaker without killing the panel.

As others have said there may well be a service disconnect outside. If there is not protection ahead of the panel, concern about the panel should increase. It would be a good idea to be thinking about replacing the panel. As you have no doubt picked up from other posts, Zinsco has known "issues".

Zinsco was bought by Sylvania long ago.

One source of information on Zinsco is:

havn't looked at the Zinsco section, but I think the section on aluminum is very good.

-- bud--

[N8N]

I am guessing if it is physically within the condo that it is probably flush mounted meaning that there will be painting and patching work needed after the box is swapped out. However, I am not stating that it's still not a good idea. I don't have any knowldge of Zinsco other than what I've heard in this thread, but if I've never heard of them how good could they be?

nate

[# Fred #]

Those breakers are spring loaded and latched in the closed position (presuming nothing is loose within the breaker or the panel) so what cause the humming from a small panel breaker?

[mattwakeling]

Thanks for all of the helpful advice. I did some looking around outside of the building and I found the metering equipment with the main power cutoff switches. The buzzing and sparking that I've witnessed in the last month or so must be the arcing. My eyes have been opened to the Zinsco problem.

Most of the wall receptacles in this place are worn out to the point where they wont hold a plug. When I replaced one of the receptacles, I couldn't find the green "ground wire" that the instructions were telling me to connect - I guess they left that wire out when they did the wiring here. From what I can tell, everything in this condo is D grade or lower. My position here is sub-renting from a sub-leaser - I have absolutely no connection to the person(s) that owns this condo, which is pretty funny. What's even funnier is that out here, this condo is probably worth 350k+.

Thanks aga> I live in a 1960's condo in Souther California. Some of the circuit

[Tom The Great]

IMHO:

There have been problems with Zinsco's, I've been told, so I would highly suggest you seek the professional advice of an electrician. Should you need a panel replacment, something you should be prepared for, get atleast three estimates, and references for work done.

hth,

tom @

[scott21230]

How old are these breakers? Breakers older than a certain age are going to be questionable irregardless of the make.

[Bud--]

The power is AC - 60Hz. With current flow a 60Hz magnetic field is produced which can cause small movement of parts within the breaker causing a hum. The field can act directly on magnetic parts, or the fields of 2 nonmagnetic parts conducting current can interact. You wouldn't hear it at low current and it wouldn't be very loud with the current likely drawn in a house panel. I have heard it on loaded 15 &

20A breakers. The sizzling sound from an arc isn't very loud either.

-- bud--

[Tom The Great]

imho:

From what I heard about Zinsco's, the problem isn't the breakers, but the panel's bus bars. So a new service panel could be the course of action. Get a professional to evaluate the condition of the panel.

later,

tom @

[# Fred #]

No humming or sizzling from my house panel even with the 240V electric range on high. I just put on a stethoscope on every breaker in the house panel an all I hear is the sound from the hot water heater pilot light transmitted through the insulated stud wall and then through the electrical panel cavity. What your hear must be a defective breaker/panel. Arching is pretty bad and its an indication of meld down temperatures much like in welding.

Yes I do hear humming in electrical switchgears (2,000A or such) but that is from the relays and respective CTs (control transformers).

[Pete C.]

Get used to sounds from the panel, the new AFCI breakers make a small buzzing sound, presumably from an internal power supply for their circuitry.

Pete C.

[Bud--]

I have located several breakers with arcing connections to the bus from fairly faint sizzling sounds - damage to the bus was apparent when the breaker was removed. I used a screwdriver as a stethescope to isolate the noise to a specific breaker. In my experience hum is not real uncommon in loaded breaker panels.

-- bud--