Chuck0
New User
- Location
- Northern California
- Occupation
- Repairman
Hi, I am new to posting on the forum here, but I have read a lot of good pointers from these very forums .
I am a general residential and light commercial repairman for about 40 years.
I have been invited many times to troubleshoot issues.
Last year I was asked to track down what seemed to be very random residential AFCI tripping, even into sub panels. All the panels are Siemens and all the breakers were Murray. There were 8 different breakers tripping. Sometimes 2 months between and sometimes the next day. Most tripping seemed to happen about an hour after dark.
I brought my TinySA spectrum analyzer to the house and found that the gas range and the range vent system both had a huge amount of wide band RF being generated even just sitting in stand-by. I put a couple of Plug in RF snubber modules in series with the plugs and I thought I had it figured out.... Well 5 weeks later another trip. I had looked long and hard at this, so I called Siemens. They suggested that I borrow their Recording Diagnostic Breaker (RDB), which I did.
Just by chance, running through the multiple trips in my head, I grabbed what I felt was the most tripped breaker and went to replace it with the RDB. When I pulled it out small burn marks were evident on the shiny relatively new stabs of the Siemens panel. Looking closely at the Murray AFCI I could see heat discoloration at the bus connection point;
. So, I cleaned the Stabs well with some fine ceramic scrubbing pad and installed the borrowed RDB. That breaker happened to be the culprit!
RDB installed completely stopped all the tripping. Now after going to the bother of requesting and having the RDB sent to me I couldn’t even use it because I couldn’t get a trip.
At any rate I bought a new, this time Siemens AFCI, replaced the RDB and solved all the nonsense tripping.
Well that was all good until this week, 5 months later, we had another set of trips within 3 second of each other. The vacuum cleaner tripped one circuit, and 3 seconds later the lights go out- both on the same phase. The owner went right out and bought 2 new Siemens AFCI breakers and I installed them this morning... and what did I find ; more burnt stabs , both on the same phase.
When I found the first burnt breaker I couldn’t get any response from Siemens concerning this issue.
Now the home owner is concerned about the overall safety of his electrical system.
I am wondering if anyone has experienced this issue in the past ?
Murray is supposed to be compatible with Siemens according to Siemens.
I hope this doesn’t become a Zinsco problem, but it will probably be ok since the AFCIs trip before they can weld on
.
If anyone has experienced this or more importantly found a cause, I would like to know. I am hoping the new Siemens breakers do the job
I’m pretty sure since the arcing was happening on the bus all the breakers were reading the noise on the line that is why such random tripping.
If I can figure out how to get pictures uploaded , I will
I am a general residential and light commercial repairman for about 40 years.
I have been invited many times to troubleshoot issues.
Last year I was asked to track down what seemed to be very random residential AFCI tripping, even into sub panels. All the panels are Siemens and all the breakers were Murray. There were 8 different breakers tripping. Sometimes 2 months between and sometimes the next day. Most tripping seemed to happen about an hour after dark.
I brought my TinySA spectrum analyzer to the house and found that the gas range and the range vent system both had a huge amount of wide band RF being generated even just sitting in stand-by. I put a couple of Plug in RF snubber modules in series with the plugs and I thought I had it figured out.... Well 5 weeks later another trip. I had looked long and hard at this, so I called Siemens. They suggested that I borrow their Recording Diagnostic Breaker (RDB), which I did.
Just by chance, running through the multiple trips in my head, I grabbed what I felt was the most tripped breaker and went to replace it with the RDB. When I pulled it out small burn marks were evident on the shiny relatively new stabs of the Siemens panel. Looking closely at the Murray AFCI I could see heat discoloration at the bus connection point;
. So, I cleaned the Stabs well with some fine ceramic scrubbing pad and installed the borrowed RDB. That breaker happened to be the culprit!RDB installed completely stopped all the tripping. Now after going to the bother of requesting and having the RDB sent to me I couldn’t even use it because I couldn’t get a trip.
At any rate I bought a new, this time Siemens AFCI, replaced the RDB and solved all the nonsense tripping.
Well that was all good until this week, 5 months later, we had another set of trips within 3 second of each other. The vacuum cleaner tripped one circuit, and 3 seconds later the lights go out- both on the same phase. The owner went right out and bought 2 new Siemens AFCI breakers and I installed them this morning... and what did I find ; more burnt stabs , both on the same phase.
When I found the first burnt breaker I couldn’t get any response from Siemens concerning this issue.
Now the home owner is concerned about the overall safety of his electrical system.
I am wondering if anyone has experienced this issue in the past ?
Murray is supposed to be compatible with Siemens according to Siemens.
I hope this doesn’t become a Zinsco problem, but it will probably be ok since the AFCIs trip before they can weld on
.If anyone has experienced this or more importantly found a cause, I would like to know. I am hoping the new Siemens breakers do the job
I’m pretty sure since the arcing was happening on the bus all the breakers were reading the noise on the line that is why such random tripping.
If I can figure out how to get pictures uploaded , I will