Why did the breaker trip after a power outage?

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Last night I was at a local tavern when the power went out in a large section of town. This was probably due to a storm outdoors. The power was only out for about 2 minutes. When it came back on, one wall containing several neon beer signs, a jukebox, and 4 video games did not come back on, while the rest of the building was fine. The bartender found that the breaker for that one wall had tripped, and had to reset it. Once reset, everything was fine.
I dont understand why a power outage would cause that breaker to trip????
My only thought is that this circuit is drawing near it's maximum amperage capacity for that breaker, and the surge of all those devices caused it to trip. Yet, if this is the case, why did it not trip when it was reset? The surge would be the same..... However, I got to thinking that when the whole section of town was turned back on, that the voltage would be low for a few seconds due to all the loads, and the lower voltage to those devices would cause then to attempt to compensate by drawing more amps...... Then the thought would be whether it's the electronics in the jukebox and video games, or the high voltage transformers on the neon signs that would draw the excess current? Does this make sense?
Anyone have any thoughts on this?
Thanks
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I may find out what the load is on that breaker one of these days. I'm friends with the owner and I might just take my amp meter over there when they are not busy and do some tests. I kind of think that breaker is overloaded. It's an old building and these days the taverns keep getting more and more electronic gadgets, plugged into old wiring. Video games and a jukebox should not use more power than a computer or stereo, but when you add them all up, it could be at it's limit, along with the neon signs. I'm not sure what a neon sign uses for power? I'd not think much, but I could be wrong. If that's a 15A breaker, it might be at it's limit.
I was planning to check out one of their florescent lights anyhow, since it keeps going on an off. Probably just needs new bulbs. I may as well check both things at once. The owner is struggling to keep the place open because of lacking funds, and cant afford to call an electrician for every little thing, so I'm happy to help. Its a small business run by good people......
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On 5/6/2012 8:39 PM, snipped-for-privacy@toyotamail.com wrote:

Neon signs use transformers do they not? Don't many use 12 volts? Maybe unbalanced current in a couple of these transformers can trip the breaker when they are fired on all at once. just a humble guess
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I do not know about the newer ones, but the old type use a transformer that puts out around 10,000 volts.
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On 5/6/2012 9:00 PM, Ralph Mowery wrote:

you might be right on the voltage. I was thinking of newer stle LED lights made to look like neon. I've looked at the labels on those, but not real neon lights...
However my guess that the transformers are failing stands. Would explain the flickering.
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LED signs are a whole different matter. They are NOT neon signs. These are the REAL neon signs. LED would draw little current.

Who said anything about flickering neon signs? I didn't!!!!
I said there is a florescent ceiling light that is going on an off, and it's not on this same circuit, so it has nothing to do with this problem. I just intend to change the bulbs or ballast (whatever it needs).
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Understood. Was not reading your post carefully, my apologies.
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On Sun, 6 May 2012 21:00:25 -0400, "Ralph Mowery"

You're correct. They put out high voltages, higher than the spark plugs in a car. I have one of the transformers and it was fun the day I got it to see how long of an arc it would throw. An inch was normal. I actually think the older ones put out even higher voltages. probably around 15kv. I know I would not want to touch it..... My livestock fences operate at 2000 to 5000kv and I know what that feels like!!!
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On 5/6/2012 7:55 PM, Duesenberg wrote:
...

...
I think most bar signs and such are designed for 120V AC plug ins but that's a guess; I never investigated. If they're old as sounds like might be from the description of the locale, the inrush current could be significant just like an electric motor as compared to operating current.
Supply voltages of 15 kV or thereabouts at mA currents. Roughly 200 W/50 running-ft of tube. Small window signs thus aren't much individually.
--
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take a clamp on ampmeter, they work well, and are now cheap to buy and easy to use
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On Sun, 06 May 2012 19:39:54 -0500, snipped-for-privacy@toyotamail.com wrote:

You could ask the owner if the breaker that controls the circuit in question gets warm. I never really used the touch test to trouble shoot, but if the breaker is warm it may be close to the trip point.

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Breakers do not always respond in milliseconds. Most common ones work by heat. The more current that is passed through them, the faster they will trip. If several electrronic devices or motors try to start back up at the same time, the breaker could be overloaded. If they are powered up one at a time,the breaker may not trip. Many devices require more current to start than they do a few seconds or so after they are startred.
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On 5/6/2012 8:59 PM, Ralph Mowery wrote:

Neon lights would be like that too. They would need more current to intialilly come on than to stay on.
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wrote:

Many common breakers are just that. Over current devices. They are not made to be used as switches and cut off and on every day. There are some made that can be used for switches.
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On May 6, 7:26pm, snipped-for-privacy@toyotamail.com wrote: SNIP

If using the breaker as a switch is ok wrt what gets turned off, a simple solution would be to wire a switch into the circuit as it leaves the panel.
This could be worked into the circuit quite easily. If all the units are on a single breaker....simple enough.
btw here is a link to QO trip curve
http://static.schneider-electric.us/docs/Circuit%20Protection/Miniature%20Circuit%20Breakers/QO-QOB%20Circuit%20Breakers/730-3.pdf
Inrush current (the best results of my internet search) for neon lights is about 3 to 5x higher than "running current". Current of 5x rated breaker current will trip a QO in .6 secs.
Sounds like the inrush to the neons could have tripped the breaker.
cheers Bob
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wrote:

t%20Breakers/QO-QOB%20Circuit%20Breakers/730-3.pdf
Interesting!!!!! Those are some hefty transformers on the neons, at least those old ones were.
As far as using breakers as switches, I used to work for a company that did maintenance for industrial buildings. One of them was a church, and they used the breaker panel for turning off all the church lights every day. In fact they taped the breakers that were not meant to be turned off (such as the ones to the offices, and ones that had computers or the furnace or AC). I thought that taping them would defeat their ability to trip as needed. The thing is that the church actually had light switches, but they were scattered all over the place, so it was easier to just flip about 8 breakers to turn everything off.
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On 5/8/2012 12:37 PM, snipped-for-privacy@toyotamail.com wrote: ...

Other than your count is about six low, you must have been here. Funny, I don't remember seeing you on Sunday mornings. :)
And no, the taping doesn't affect trip; the handle doesn't need to move externally for the breaker to trip (and the tape isn't strong enough or have enough grip to stop it anyway); it just serves as an indicator of the "noninterruptible" circuits.
--
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On 5/8/2012 12:49 PM, dpb wrote:

...
In this panel, however, for most circuits there are no switches. A couple of circuits that service entry stairwells, hallways, etc., are switched (and stay on) but the sanctuary lighting and all are not.
As are many commercial building main lighting circuits; there are some switched for ingress/egress purposes but often the bulk is controlled from the panel.
--
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On 5/8/2012 12:37 PM, snipped-for-privacy@toyotamail.com wrote:

it's a very common practice in commercial places.
--
Steve Barker
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On Tue, 08 May 2012 18:00:14 -0500, Steve Barker

The breakers should be rated to be used as a switch, though. https://www.google.com/search?q=switching%20duty&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&source=hp&channel=np#hl=en&safe=off&client=firefox-a&hs Z&rls=org.mozilla:en-US%3Aofficial&channel=np&sclient=psy-ab&q=switching+duty+breakers&oq=switching+duty+breakers&aq=f&aqi=g-v1&aql=&gs_l=serp.3..0i15.10305.12941.0.13068.9.3.0.6.6.1.1499.1746.0j2j7-1.3.0...0.0.BrZR_ml-uk4&pbx=1&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.,cf.osb&fp407b5897f76374&biw1&bihR5
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