Fuse box flipping

[Fryar]

Our disposal stopped working, so we tried resetting it. That didn't work, so my husband went crazy flipping the fuse box switches back and forth. Now our built-in microwave is not working. Could he have shorted it out when he was going crazy with those switches? It's less than a year old.

 

[Howdie]

I guess this could happen, but maybe there was some kind of short somewhere? I'd get a licensed electrician to check things out just in case there's a fire hazard somewhere. I'm always too, too careful when it comes to electrical wiring, especially in older houses.

 

[HayZee518]

People use the term "short" at the most inappropriate times. If a circuit trips a breaker it's always a short. It could be over current too! A direct short may or may not have arcing present, but ti does trip a breaker. If you turn on a breaker and nothing happens, it is called an "open" there is an open circuit someplace.

 

[Nifty]

HayZee, that's a great point!

I don't know a lot about breakers, but I assume that they have to allow enough current for things to run with enough amperage, but also not allow too much amperage that things overheat and cause other problems, correct?

 

[HayZee518]

a circuit breaker is engineered to trip out within three cycles of alternating current on overload. a problem breaker from "square one" are the federal Pacific types. We had a test setup for checking out breakers in the power plant. we hitched up a 15 amp federal to the test set and fed the over current into it. after the required three cycles it still didn't trip. we increased the current and after a lot of smoking it finally tripped after eight times the fault current went through it.

 

[Nifty]

Very interesting!!!

Are breakers at all designed to protect people if/when they are using their bodies (accidentally) as a short? I guess someone would still get enough current to be a problem before the breaker trips, right?

Do GFCI's offer this kind of protection... I mean if something down the line shorts, it will trip?

 

[Montyj]

No. Breakers will not protect people from electric shock. Breakers work on an over-current principle, where GFCI's work on a current comparison principle. A circuit breaker will normally contain either an electromagnet, or a bimetallic switch that will trip the breaker when the current exceeds the breakers rating. Unfortunately for people, that means the entire tripping current would pass through the body until the breaker trips. A GFCI compares the input current to the output current (hot to neutral) which should always be equal. If there is a difference of more than a few milliamps, it trips open.

You can string devices down line from a GFCI and they will also be protected if wired correctly. In fact, that is how my pool outlet and DW's gazebo are wired. The gazebo outlets are protected by the GFCI at the pool outlet.

 

[Nifty]

I mostly hear about GFCI's being used around water, but wouldn't they be good in other uses as well? Maybe I'm just misunderstanding what they protect against?

 

[Montyj]

GFCI's protect against electric shock. You can use them where ever you want. I also have one behind the fish tank. THe most common causes of electric shock are appliances used around water. Today you can buy GFCI breakers for a breaker panel.

 

[Nifty]

On my remodel I'm thinking about sticking in a few GFCI's and then running outlets down the line off of them. I don't know of any downsides to doing this other than GFCI's being a bit more expensive than regular outlets.