Main Service Panel Breaker tripped

[Greg Peterson]

So I come home this evening and the power is out in our house and the neighborhood. Just out of habit, I go check the service panel to confirm power is out in the house. Open the door on the panel and the 200 amp mains is tripped. I also see some scorching on the inside of the panel door, right about where the surge arrestor is located.

Curious and concerned, I pull the cover on the panel and see that the GFCI breaker is burned out (black soot on the copper bus, neutral wire discolored). The AFCI breaker adjacent to it was fine however. The surge arrestor I installed about three weeks ago is definitely burned out.

Questions:
1. What would cause the mains to trip when there was no no load (no one was home. Aside from a fridge or other electrical vampires no draw of appreciable amount-certainly nothing like right now).

2. What would cause the GFCI to burn out but leave the AFCI intact?

3. In the process of absorbing/suppressing a surge, could the surge suppressor cause the GFCI to burn out?

The surge suppressor installs on the bus and straddles both sides of the phase (two space). I'm assuming this particular unit has a sacrificial carbon link. There are two LED's on the unit and instructions say to discard the unit if the lights are not on. I'm guessing sink the unit scorched the panel (slightly) and the LED's are covered in soot, the unit is literally toast.

4. Any recommendations for a service panel surge suppressor that is perhaps a little more robust.

Aside from the surge arrestor and GFCI breaker, the only causality is our coffee maker. Seems the surge arrestor didn't quite do its job or the maker was not engineered to withstand much of a hit. Everything else in the house is working, including my cheap little clock radio.

[Rod Sheridan]

Surge supressors work by becoming conductive when the applied voltage exceeds a certain level.

The suppressor then draws current, in proportion to the amount of overvoltage. Suppressors often fail catastrophically, and as such should be located in seperate steel enclosures.

The suppressor obviously absorbed a significant surge, and the resulting flash over of conductive material and plasma caused an arcing fault inside your service panel.

The main breaker either tripped during the conducting period of the suppressor, or during the flash over event. Have the panel evaluated by a competent person, who can perform an insulation resistance measurement on it. The panel may be compromised enough to require replacement. Visual inspection is not adequate.

At the same time, ask them about re-locating the supressor to a seperate enclosure. Install a warning lable on the supressor door to indicate that power must be disconnected before opening the door.

Imagine what would have happened if your face had been in front of it when if failed.

Regards, Rod.

[Matt Meiser]

I know nothing about these, but I've got to wonder if the surge supressor shouldn't be investigated further. New surge supressor + strange event makes me wonder if it isn't the culprit rather than the victim. Doubt that would have taken down your whole neighborhood though. Anytime I see a change in a system followed by a strange event, I am always suspicious of the change.

Have you talked to any of your neighbors to see if they have damage?

- Matt, who has a BSEE, but who has only ever done software engineering and didn't do so hot in his power class 12 years ago.

Edit: Due to the fact that my software talks to industrial equipment and I sometimes have to open control panels, I've had to take electrical safety training. Rod is right on about the danger of the thing blowing up in your face. There are numerous examples of someone who was using something as simple as a meter and had it blow up in their hands when a surge hit. You can never know when that is going to happen and it happens so fast you wouldn't even have time to blink when it does. There are some devices that are banned from Ford facilities (and I'm sure others with strong safety programs, but our trainer was one who helped Ford set up their program) because the danger is that high.

[David G Baker]

Greg,
Lightning can cause your problem but more than likely it was an accident involving a power pole. Vehicles hitting power poles can cause a lot of damage to power equipment in the surrounding area.
Where I once lived in California a truck hit a utility pole in a commercial area and caused tens of thousands of dollars damage to several companies electronic equipment. The utility company was sued, lost the suit and had to reimburse the companies for their losses.

[Greg Peterson]

Thanks for the input guys.

The neighborhood lost power. I checked with my neighbors and they all were without power as well. I checked one neighbors service panel to see if there were any tripped breakers or mains, and did not find anything tripped.

I was very surprised to see the flash over damage. I did not expect the surge suppressor to be so explosive, although in hindsight I understand. The instructions never indicated the violent nature of this device, but since it isn't a consumer grade/DIY type product, I guess a qualified electrician would know that the unit should be isolated. It's interesting to note however that the documentation stated that it was compatible with my service panel.

Lesson learned.

[Jim Becker]

This past Friday, at about 11am, a pole just south of our driveway "exploded", causing two or three levels of high voltage lines to cross. A very healthy surge hit our house...scared the you-know-what out of me sitting here in my office. The road was closed from 11am through about 3 am the next day while the power company PECO and Verizon reconstructed things. For about two hours, power was off clear into Doylestown including Professor Dr. SWMBO's office...nearly 8 miles away! The local cell site was also down during that time. A number of breakers in the main panel let go, three surge protectors and my beloved office voltage regulator gave their lives in that hit. (My two new UPSs and several surge protectors just arrived from Amazon...)

[Matt Meiser]

Look at the bright side Jim: No phones, no internet, no power, no work, right?

Of course no shop either.

[Jim Becker]

Look at the bright side Jim: No phones, no internet, no power, no work, right?

Of course no shop either.

Yea...and after wending my way around the police barricades to drive to Professor Dr. SWMBO's office in hopes of working there...the power was out, too. So we went out for Mexican...it was lunch time. Unfortunately, I really had some work that needed done on Friday since I'm in training three days this week on some SIP and SOA stuff. That said, the Dos Equis that wasned down the meal was delicious...:D (The $300+ in new UPS and surge protection, however...)

[C Scott McDonald]

I have to ask. being new to the site.. what the heck does "SWMBO's " mean anyway?

[Ken Fitzgerald]

She Who Must Be Obeyed.................

[C Scott McDonald]

She Who Must Be Obeyed.................

Wow, would have never figured that out. Thanks

[Tom Veatch]

Wow, would have never figured that out. Thanks

Must not have been a fan of the series on PBS "Rumpole of the Bailey"(sp?). He was an English barrister who never refered to his wife except as "She Who Must Be Obeyed".

[Jason Roehl]

Yea...and after wending my way around the police barricades to drive to Professor Dr. SWMBO's office in hopes of working there...the power was out, too. So we went out for Mexican...it was lunch time. Unfortunately, I really had some work that needed done on Friday since I'm in training three days this week on some SIP and SOA stuff. That said, the Dos Equis that wasned down the meal was delicious...:D (The $300+ in new UPS and surge protection, however...)

My only question is this:

Was it a Dos XX lager or Dos XX amber? :D

With Mexican food, I usually go for the Negro Modelo...

[Jim Becker]

Amber, Jason. I prefer the darker brews; especially the Belgians at my local brew pub. (but only about one per week...) I always forget about the Negro Modelo for some reason...

[Rod Peterson]

I have to ask. being new to the site.. what the heck does "SWMBO's " mean anyway?

I have a page on my site devoted to more explanation than you probably ever dreamed you needed.

woodbutcher.net (http://www.woodbutcher.net)

[Randal Stevenson]

Look at the bright side Jim: No phones, no internet, no power, no work, right?

Of course no shop either.


Yea...and after wending my way around the police barricades to drive to Professor Dr. SWMBO's office in hopes of working there...the power was out, too.


Off to the neander forum with the two of you! :D

[Jack Briggs]

My only question is this:

Was it a Dos XX lager or Dos XX amber? :D

With Mexican food, I usually go for the Negro Modelo...



I'll second the Negra Modelo!

[Hank Knight]

Greg,

Look at the bright side: if you didn't suffer any other damage to your household electrical equipment and appliances, the surge protector did it's job. We got hit by lightning a couple of years ago (no surge protector) and the jolt destroyed every piece of digital equipment in my house. It even fried a couple of magnetic switches in my workshop. It took months to get it all straightened out.

Hank

[Bruce Wrenn]

This past Friday, at about 11am, a pole just south of our driveway "exploded", causing two or three levels of high voltage lines to cross. A very healthy surge hit our house...scared the you-know-what out of me sitting here in my office. The road was closed from 11am through about 3 am the next day while the power company PECO and Verizon reconstructed things. For about two hours, power was off clear into Doylestown including Professor Dr. SWMBO's office...nearly 8 miles away! The local cell site was also down during that time. A number of breakers in the main panel let go, three surge protectors and my beloved office voltage regulator gave their lives in that hit. (My two new UPSs and several surge protectors just arrived from Amazon...)Did you file a claim with power company for your losses, due to their equiptment failure. If this was caused by a car, call police and get a claim into driver's insurance company. Most never think to do this, but that is what ins. is for.

[Jim Becker]

Bruce, it was an act of nature...heavy winds, etc. And filing a claim on some nearly 18 year old power conditioning equipment that I mostly got for free (samples from TripLight when I was selling systems) really wouldn't fly. But I do agree that insurance is there for appropriate events when they happen.