Circuit breaker test

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DIY

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With my electrical experience of just betwwen novice and almost intermediate I have never heard of a circuit breaker that can be tested unhooked out the breaker box with a neon light tester..? This was told to me by a youngin at an Ace hardware store. Was not sure about that so i thought i'd check with some folks that would know for sure here. 20 amp single pole circuit breaker that needs to be tested. Thanks all
 

Lightwave

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Circuit breakers cannot be tested for adequate (i.e. safe) trip performance without specialized equipment.

What's the problem you're trying to fix?
 

hj

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A continuity tester can tell if it makes and breaks properly when the switch it thrown, but NOTHING that you have access to will test its amp rating to trip automatically. You used two words in your question, "Youngun", and "Ace" that pretty much precluded that being reliable advice.
 

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Well i knew from the get go Ace is not the place....but hell it was right next door to starbucks where i was initially.
 

DIY

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Lightwave the problem is there is an appliance and 2 outlets on this circuit. I am getting no power at any three of those. The breaker did not trip apparently at least the switch did not exemplify that of tripping. I toggled the switch back and forth on the breaker a few times...nothing,so what i wanted to check next was the circuit breaker if good or not which brought me here. Good news earlier today i went ahead and just bought a replacement breaker a ta very resonable price $3.98 to my suprise at home big house- hooked that up and power was restored at the 2 outlets and appliance right away.
 

Lightwave

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For future reference:

You can check a breaker for continuity simply by using a voltage checker (or volt meter) between the CB's terminal screw and the breaker box neutral bus. A breaker that does not show voltage when in the 'ON' position is--unsurprisingly--defective. Conversely, a breaker that shows voltage at its terminal(s) when turned off is severely defective and should be removed immediately.

If you have an ammeter you can measure the amperage draw on a given circuit at the breaker. This can be used to determine if a breaker that trips regularly is tripping due to a real excess load or due to a malfunction. E.g. a 15A breaker that trips when subjected to a measured load of 12A is defective, as would be a 15A breaker that holds a 20A load indefinitely.

These are the sum total of circuit breaker field tests. Anything more sophisticated--for example, proving a circuit breaker to be functional--means sending the breaker to a lab. Field testing can identify some kinds of breaker defects but is not assured to identify all kinds of breaker defects. If there is any doubt regarding a circuit breaker's functionality, it should be replaced.
 

CodeOne

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For future reference:

You can check a breaker for continuity simply by using a voltage checker (or volt meter) between the CB's terminal screw and the breaker box neutral bus.
.

Just a thought make sure you use the voltage setting on the meter and not the continuity (ohms/resistance) setting. You would burn your meter up at the very least and could cause the battery to explode.
 

Jadnashua

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Depending on its use, the curve of a circuit breaker (i.e., when it trips) can vary quite a bit. For example, one designed for a large motor (say an a/c compressor) might be designed to allow momentary significant over current before it trips. More general use ones, may only allow a much shorter overload. Then, they can be designed to trip at sustained loads at various levels and after various times. So, first you'd have to know what the curves were that it was designed to, then proving it takes some equipment few people have in their home workshop.

It's not a bad idea to have a few spare CB around, since like anything mechanical/electrical, they do break occassionally. Sort of like the idea of having some spare fuses, back when those were the primary safety device.
 

Karl Ess

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Spares ??? I used to use pennies behind the blown fuses.
Now, I use a bungee cord through the breaker handle to hold it in the 'on' position.
Hey folks, I'm just joking, please don't try. But those crazy folks who think that
hair pins & racing (duct) tape will fix anything are out there. BEWARE.
 
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