Zinsco Mystery

Status
Not open for further replies.
Re: Zinsco Mystery

Originally posted by hmspe: An electrician tested all the wiring in the house and found no problems or mis-wiring of any kind.
Click to expand...
By any chance, is the 20/1 breaker feeding the receptacle powered from the same bus as the side of the 200/2 that has failed? If so, does it have power? When your electrician tested "all the wiring," did that test include the internals of the panel?

What I am suggesting is another possible explanation: that the entire bus may be dead. Supposing that the 20/1 is off the other bus, and is working. What that means is that you have no loads that are powered by the failed side, and that you could turn on, in an effort to see if the bus itself has power. It could be a simple as a loose connection that was jostled during installation of the feeder to the range.
Originally posted by hmspe:. . . that just happened to pick an odd moment to fail.
Click to expand...
Actually, I think the most likely times for something to fail are when you turn it on for the very first time, and when you turn it on the first time after you have changed something.
 
Re: Zinsco Mystery

Charlie,

I haven't examined the installation myself, so I can't say. The report was that both legs had power on the line side but the 200/2 only had power on one leg on the load side.

This is a friend's cabin that's 75 miles away. I did the design and helped with the wiring. The cabin has been under construction for over 2 years and is finally coming up for final inspection. As might be expected, the incident happened Thanksgiving day.

Martin
 
Re: Zinsco Mystery

Hi Charlie,
As an installer of many a Zinsco Panel in the early 70's, the R38 Twin has the bus tabs that are reversible. If either tab screw on the underside is loose, it can do mysterious intermittant tricks. Most Zinsco flaws are of an intermittant function that can arc open a loose joint momentarily...similar to a loose neutral.
If the breaker is temperature hardened from intermittant cycling, replacing it with an aftermarket Challenger equivalent may be an answer.

rbj, Seattle
 
Re: Zinsco Mystery

[QUOHe removed the breaker and tested it.TE] [/QUOTE] How in the world would he have tested that breaker???? I understand the apparatus used in testing breakers, whether 20 amp lighting panel size or distribution size is rather advanced and trained personnel are the only people who should do this, not "Landlords".

Maybe I'm all wet but I'm from an outfit where we employ "Power Services" personnel who stay current on testing procedures and are trained to operate timed/overcurrent testing equipment.

Could you tell me how your breaker was tested

THanks

Steve
 
Re: Zinsco Mystery

Originally posted by sundowner:Could you tell me how your breaker was tested
Click to expand...
I didn't ask that question, so I would only be guessing at an answer. But it would not have involved verification of the breaker's ability to setpoint, let alone its trip setpoint. My guess is that the test was merely verification of continuity when closed, along with a visual inspection.

It's been a week, and the problem has not come back.
 
Re: Zinsco Mystery

Sounds like you have a problem with an open neutral which won't trip a breaker but will turn the lights off if the neutral for everything that went out is daisy-chained instead of parallel at the switch. Does the light that you turned on have two switches associated with it?
 
Re: Zinsco Mystery

The light switch that "broke the camel's back" was a single pole, single throw switch that turned on a single light in a small bathroom. There is no other switch and no other light in that bathroom.
 
Re: Zinsco Mystery

I think you might be missing my point Charlie.

In response to Paul's mention of the light bulb being to small of a load to be suspect of causing a poor or failing connection to open completely, I was pointing out that a 100 w. bulb "starts" significantly harder than an amp.
 
Status
Not open for further replies.
Top