Lightning tripped all breakers?

[hockeyoligist2]

The other night one of our plants had a power outage. When I arrived all of the breakers were tripped except the main in the generator switch gear building.

The breakers feed the individual buildings. I checked for faults and everything checked OK, so I reset them and everything started back up. No damage anywhere that I could find.

Some storms were in the area about the time of the power loss. Think it was Lightning?

 

[mdshunk]

Any of the breakers involved have accessories that can trip them?

 

[hockeyoligist2]

Any of the breakers involved have accessories that can trip them?

No. They are coordinated to trip before the main. Lower trip settings. Nothing extra. What is strange to me is the fact that all six of them tripped? None of the mains or anything in the separate buildings tripped.

I'm thinking, actually hoping, it was lightning!

 

[LarryFine]

You sure someone didn't do it without asking or telling anyone else?

 

[catchtwentytwo]

You sure someone didn't do it without asking or telling anyone else?

This likely happens more than anyone realizes.

 

[mdshunk]

This likely happens more than anyone realizes.

I think that's right. It's pretty often that I've faced with one of those older 12 and 16 circuit panels that had two rows of horizontal breakers. For them all to be 'on', one row needs to be flipped up and the bottom row needs to be flipped down. The trouble call is normally for a bunch of circuits with no power. When I look at the panel, both rows of breakers are flipped 'up', making the whole bottom row 'off'. Naturally, everyone swears nobody touched it. Must have been Casper, huh?

 

[hockeyoligist2]

I don't think anyone could accidentally trip this type of breaker.



It was also late at night, no one there. Gates locked.

 

[brian john]

--------------------------------------------------------------------------------

I don't think anyone could accidentally trip this type of breaker.

WANT TO BET!


I have seen a few instances where lightning resulted in numerous trips of CBs not all CB but some here some there. But depending on the magnitude and duration and number of strikes.......

 

[hockeyoligist2]

WANT TO BET!


I have seen a few instances where lightning resulted in numerous trips of CBs not all CB but some here some there. But depending on the magnitude and duration and number of strikes.......

I think it was from lightning too Brian. What I meant is if someone accidentally tripped one of these, they would know it! I still jump when I push the button!

I was referring to the above posts, the ones I'm dealing with aren't the same as the type they are referring to.

 

[mxslick]

Might want to look a bit closer...

Might want to look a bit closer...

No. They are coordinated to trip before the main. Lower trip settings. Nothing extra. What is strange to me is the fact that all six of them tripped? None of the mains or anything in the separate buildings tripped.

I'm thinking, actually hoping, it was lightning!

I think the breaker's trip electronics responded to the impulse from the lightning and sent a trip command. Or if they have phase loss or undervolt trip the lightning could have easily caused a sag or dip on one or more phases from the utility.

If the strike was close enough it may have also damaged the trip units as well.

It would probably be a good idea to schedule a test of all of the affected breakers to make sure they're ok.

 

[hockeyoligist2]

It would probably be a good idea to schedule a test of all of the affected breakers to make sure they're ok.

I set the test up Friday. The tech guy checked them out this morning. He said they are OK, most likely it was lightning and they had done their job.

 

[brian john]

I set the test up Friday. The tech guy checked them out this morning. He said they are OK, most likely it was lightning and they had done their job.

Did they have a shut down to check these devices.

 

[quogueelectric]

Drill a padlock in the closed position to keep this from happening again.:wink::grin:

 

[zog]

I set the test up Friday. The tech guy checked them out this morning. He said they are OK, most likely it was lightning and they had done their job.

What exactly did he test? I doubt he did any injection testing if he did them all this morning himself. MX has a point that the trip units may be damaged, these types have precautions about meggering the breakers and causing trip unit damage, lightning is one big megger and could have easily damaged the trip units.

 

[hockeyoligist2]

Did they have a shut down to check these devices.

Yes, one building at a time.

 

[hockeyoligist2]

What exactly did he test? I doubt he did any injection testing if he did them all this morning himself. MX has a point that the trip units may be damaged, these types have precautions about meggering the breakers and causing trip unit damage, lightning is one big megger and could have easily damaged the trip units.

I was only there for a few minutes. I left him with his helper. He is the factory Tech. I do know he did a Hi-pot, and meg test on one, before I left. He is always thorough with his inspections, he is our "go to guy"for breakers. The equipment is still under warranty. I'm sure he checked everything.

 

[zog]

I was only there for a few minutes. I left him with his helper. He is the factory Tech. I do know he did a Hi-pot, and meg test on one, before I left. He is always thorough with his inspections, he is our "go to guy"for breakers. The equipment is still under warranty. I'm sure he checked everything.

He hipotted your 480V breakers? If they werent fried before they are now. Factory tech dosent mean anything, I would really like to know what tests he did. Primary injection? Contact resistance?
Did he provide test reports?

 

[hockeyoligist2]

He hipotted your 480V breakers? If they werent fried before they are now. Factory tech dosent mean anything, I would really like to know what tests he did. Primary injection? Contact resistance?
Did he provide test reports?

I'm not qualified to doubt his ability, I will get a report from him in about 2 weeks on the exact tests and results. I have a lot of confidence in his work. Factory Tech under warranty means a lot to me. It is his equipment, if he makes a mistake.... he eats it.

 

[zog]

I'm not qualified to doubt his ability,

That can be a problem. please post some test results when you get them and we can evaluate.

 

[weressl]

The other night one of our plants had a power outage. When I arrived all of the breakers were tripped except the main in the generator switch gear building.

The breakers feed the individual buildings. I checked for faults and everything checked OK, so I reset them and everything started back up. No damage anywhere that I could find.

Some storms were in the area about the time of the power loss. Think it was Lightning?

Lightning can cause this in many different ways. Unless you have high speed data recording in the trip units you can fawgetabout trying to figure out HOW they tripped. This is the classic example of nuissance triping. It could have been line imposed spike due to EMP, or inductive coupling. It could have been EMF or EMP on the board or chip level, who knows.

The more troubling of these type of failures that the initiator could also have stressed the electronics and down on the line it will inexplicably fail. I don't think anybody has a surefire method of chasing these problems down. Designing electronic circuits with voting elements, where 2 out of 3 or more have to 'agree' in order to act had success in inductry and also in aerospace applications.

In sort, keep an eye on those trips for awhile.