Limitations of Circuit Breakers & GFCI's

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TVH

Senior Member
Will a circuit breaker trip if a person contacts the neutral and hot wire at the same time?
What about same situation for a GFCI?
Is there a list out there that summarizes what CB & ELCB's will and will not do?

Thank you for your time.
 

peter d

Senior Member
Location
New England
A "normal" circuit breaker would likely never trip until you are cooked meat. Same with a GFCI breaker unless some of the current leaked somewhere other than through your body.

Basically, a normal breaker trips slightly above its handle rating, as does the normal breaker part of a GFCI breaker. So, a typical 15 amp breaker would allow many times the amount of lethal current to flow before it ever trips, which it would have no reason to do unless there was a sustained overload or a short.

Since the GFCI portion trips with current imbalance only, as long as there is no imbalance with the current that happens to be flowing in one arm and out the other, it won't trip either.
 

mdshunk

Senior Member
Location
Right here.
Will a circuit breaker trip if a person contacts the neutral and hot wire at the same time?
Probably not, unless that person is made of something other than flesh.
What about same situation for a GFCI?
Yes, it will trip if you happen to be touching something else at the same time. If not, you're still cooked.
Is there a list out there that summarizes what CB & ELCB's will and will not do?
No list required. They trip when the time-current exceeds the rating of the breaker, in accordance with the published trip curve. The GFCI will trip when the time-current exceeds the published trip curve, or when the ground fault exceeds the UL mandated time and current limits.
 

Karl H

Senior Member
Location
San Diego,CA
If you make contact with a hot and neutral and nothing else the
breaker or GFCI will simply allow the current to flow.You become
a load not a fault.
 
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