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Default Can I test to verify amp rating on a circuit breaker with a multimeter

Default Can I test to verify amp rating on a circuit breaker with a multimeter

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Old 04-08-09, 12:01 AM
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Default Can I test to verify amp rating on a circuit breaker with a multimeter

My circuit breakers have red stickers on the switches showing the amp rating (20 amp and 15 amp). I would like to verify that this is correct. Can I use a multimeter to test this? If so, do I test this at the panel at the wires coming out of the breaker or at a receptacle that is connected to that circuit?
 
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Old 04-08-09, 04:58 AM
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Why in the world would you want to "Verify" a rating placed there by the manufacturer? They are individually tested prior to being placed on the market. If you have a question of a breaker, replace it. But to answer your question, no you can't test a breaker with a multimeter.
 
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Old 04-08-09, 05:48 AM
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Hi toolmonkey, sometimes people want to know how much load is on a breaker, and even for that a multimeter would be challenged to give you a reading of any value. Just look at the test leads, they were never intended for 20 amps.

Then, understanding breakers, they have a fairly large tolerance to variations in load. A 20 amp breaker might handle 30 amps for a very short duration, but might take minutes to trip at 21 amps. These are not the correct numbers, but there are wide variations. But, as Chandler said, they are all tested at the factory and designed to high standards because their function demands it. As stated, if you have some you question, replace them and you can have a high confidence the new ones will function as intended.

Now, if you are having a problem that is prompting this question, post it and the electricians here (not me) are very good and can help.

I have to comment that you chose your handle well
Bud
 
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Old 04-08-09, 07:54 AM
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Toolmonkey, are you sure the rating isn't on the face of the switch that's for the breaker. If it isn't then it's a very old breaker and then I would just replace them to be safe. Sent us a picture of it and maybe we can help locate it on the breaker.
Jim
 
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Old 04-08-09, 08:05 AM
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What you can do is load up the circuit to see when it trips. Keep your fire extinguisher handy!

Or, you can contact the mfr to see if they can give you the UL or other test data on the breaker.

If you suspect your breaker is bad, it would be cheaper and easier to replace it with an identical one.

To make a decent ammeter, you can get an "amp clamp" that places a current transformer (CT) around the hot wire. The amp clamp lead plugs into your multimeter. You then multiply the value on the meter readout by a factor specified in the amp clamp's instructions and voila, that's your amperage.
 
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Old 04-08-09, 08:11 AM
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I know I *should* replace my panel, but I currently do not have the money to do this. Its an old FP, which I was told is *crap*.

See image below, the ratings are red stickers. It may also have a rating on the side, but its hard to see since its recessed in the sheetrock.

http://img.photobucket.com/albums/v1...e/IMG_5756.jpg
 
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Old 04-08-09, 09:50 AM
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Originally Posted by toolmonkey View Post
I know I *should* replace my panel, but I currently do not have the money to do this. Its an old FP, which I was told is *crap*.

See image below, the ratings are red stickers. It may also have a rating on the side, but its hard to see since its recessed in the sheetrock.

http://img.photobucket.com/albums/v1...e/IMG_5756.jpg
toolmoney, They look like they are FP's. If they are the stab-lok type they are a fire hazard. I believe the new breakers they make have a white label on them and they are safe. If it was me I would replace the panel and breakers. Maybe see what evryone else has to say.

Jim
 
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Old 04-08-09, 09:57 AM
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Originally Posted by rukkus11 View Post
toolmoney, They look like they are FP's. If they are the stab-lok type they are a fire hazard. I believe the new breakers they make have a white label on them and they are safe. If it was me I would replace the panel and breakers. Maybe see what evryone else has to say.

Jim
Yes, I want to replace the panel. It was recommended to replace when we moved in 2 years ago. When my wife gets out of college at the end of the year, I plan on getting it replaced by an electrician (since I cant do it myself).
 
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Old 04-08-09, 10:13 AM
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Originally Posted by toolmonkey View Post
Yes, I want to replace the panel. It was recommended to replace when we moved in 2 years ago. When my wife gets out of college at the end of the year, I plan on getting it replaced by an electrician (since I cant do it myself).
As for now just don't put a big load on the breakers. Here's a site that will give you some information about your panel.

Federal Pacific Electric Panels: Fires Waiting to Happen, Debate Waiting to Be Ended


Jim
 
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Old 04-08-09, 10:24 AM
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Originally Posted by rukkus11 View Post
As for now just don't put a big load on the breakers. Here's a site that will give you some information about your panel.

Federal Pacific Electric Panels: Fires Waiting to Happen, Debate Waiting to Be Ended


Jim
Yea, I came across that site a couple of years ago. Did FP go out of business because of this? It seems like a major recall would have happen. If the danger is this bad, it would have been mandatory to change the panels out. Whats the background story on this?
 
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Old 04-09-09, 01:24 PM
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FP USA did.

The Canadian division kept on, and is currently owned by Schneider Electric, whom active sell newer Stab-lock panels and breakers to the Canadian market.
 
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