Want to test circuit breakers?

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Wuzzat?

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This,
http://www.google.com/search?q=well....7.0....0...1ac.1.34.img..0.7.329.lHkYDmzAytQ
plus a clampon ammeter plus varying lengths of copper wire (to use as an adjustable resistor) will let you do it.

These guns can put one or two hundred amps through the tip but at these current levels you can't use clip leads for your test setup, only screw terminals or small C clamps.

And buff all connections with fine sandpaper first.
 
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Testing circuit breakers is simply not a DIY job. Licensed Journeyman electricians would not be capable of properly testing a circuit breaker in the field. Circuit breakers have performance criteria that are usually expressed in a trip curve. How fast they trip is the result of how they are manufactured. A 15 ampere breaker will put up with a 16 amp load for quite a long time. The same breaker will trip almost instantaneously on a 30 ampere load. Testing that breaker for how fast it trips under what condition is done with rather expensive equipment. The only kind of premise that is likely to resort to on site testing is a large industrial plant.
 
The DIY version uses trip curves and a soldering iron (or 3 10A loads and 120v from your elec. dryer socket).

I guess the assumption here is that it's good or bad with little in between, a kind of go/no-go test.
The trip curves show pretty wide ranges, so how much precision is needed?

A little investment usually gives imprecise results, a large investment
is done with rather expensive equipment.
usually does better.

The CB makers can shed some light on whether that assumption holds up, if their lawyers will allow them to even talk to us common folk nowadays. . .:p

The one I e-mailed said they test their breakers 10,000 times with full load and 10,000 times with no load, but this is a slightly different question.
 
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The DIY version uses trip curves and a soldering iron (or 3 10A loads and 120v from your elec. dryer socket).

I guess the assumption here is that it's good or bad with little in between, a kind of go/no-go test.
The trip curves show pretty wide ranges, so how much precision is needed?

A little investment usually gives imprecise results, a large investment

usually does better.

The CB makers can shed some light on whether that assumption holds up, if their lawyers will allow them to even talk to us common folk nowadays. . .:p

The one I e-mailed said they test their breakers 10,000 times with full load and 10,000 times with no load, but this is a slightly different question.

I think most home owners just want one test. Does it work?
 
Does it work?
Try it with one or more known-good CBs. Larger samples give better confidence in the test reliability.

Face protection is recommended unless you're out for a rugged look.

Getting the correct trip curves is probably the hard part.
 
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I honestly do not understand why you Wuzzat are even posting this to begin with?

Please remember that this is a forum for DIYers not professionals. As it is, we have to be very mindful of OPs that post, mainly because their skill levels are not near a professional and that is why they come here to get advice hoping to make their project turn out safer and hopefully to code.

By posting this information you may be encouraging a DIYer to perform this test which can be quite dangerous for someone of little to no skill without them even knowing that. Most times we have to worry about if the person even feels comfortable enough to remove the breaker panel cover and by posting this you almost make the whole thing seem so simplistic that a DIYer not knowing any better who reads this and has an issue with a breaker maybe not functioning correctly will take the information and do the testing and maybe end up hurting themselves.

I say to any DIYer if you think that you have a breaker that is malfunctioning that you "simply replace it" (if you can't then hire an electrician to do it) "safety first!!" - the cost of a brand new breaker is far less of a cost than a horrible accident attempting to test the reliability/functionality of a breaker you think may not be working correctly.
 
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I honestly do not understand

1. Because I'm hoping someone who browses the Net looking for ways to reduce uncertainty in electrical troubleshooting may benefit?

2. Because I'm a showoff?

I hope my reason is greater than 70% for the first one and less than 30% for the second. And I'm working on reducing the second reason.

BTW, if an adult DIYer smokes or rides a motorcycle, the DIY project danger is usually down in the noise.
 
1. Because I'm hoping someone who browses the Net looking for ways to reduce uncertainty in electrical troubleshooting may benefit?

Then make it known in your post that your "suggestion" should only be followed by a professional and not a novice or DIYer for safety reasons please.

2. Because I'm a showoff?

So to "Sprout your wings" and show off you think it is worth the chance that someone may without realizing the danger actually follow this suggestion of yours and possibly hurt themselves or someone working with them?

BTW, if an adult DIYer smokes or rides a motorcycle, the DIY project danger is usually down in the noise.

And this makes no sense to me at all!

Be responsible please! Working with electricity is not a game and can actually "KILL SOMEONE" !!!!
 
You have my permission to edit my posts.
 
For some reason I can't read PMs. Maybe it's my old browser.


And this makes no sense to me at all!

Well, we're talking about risk.

And since I mention two things that are for sure risky, maybe it's a statement about relative risk, the risk incurred by doing DIY vs. other things.

And since everyone deals with risk every day, I would highly suggest Afjes that if you are going to be talking about risk that you take some time on your own and do some study work on the internet and learn some basics of everyday risks and relative risk. Like how dangerous is it to smoke vs. driving any kind of motor vehicle vs. other things.
It will save you a lot of other reading and confusing yourself in the long run.
Learn the basic terminology; for without the proper terminology you will not be able to follow the proper logic needed in order to persuade others and you may end up scaring someone unnecessarily.

And have you forgotten we have a disclaimer notice?
 
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For some reason I can't read PMs. Maybe it's my old browser.

Wuzzat I sent you a pm today and you are saying you cant read it because you have an old browser. I don’t really want to air in public what I said in that post but I will tell you I suggest you read it before you keep posting.

If for some reason you cant open a private line of communication between yourself and me then we will have to talk here.
 
Browser: upgrading is a treadmill with the speed set by high-rolling CEOs.
I'm not climbing back on.

When this expensive piece of junk that I'm sitting in front of becomes too inconvenient to use, I can go to any library or hotel lobby if I want Net access.

>air in public
Air your grievance, we're all adults here.
But if you somehow find out my real name and post it, you may find yourself and this forum in a courtroom as defendants in a cause of action for defamation.

>I suggest you read it
Threat or warning?

Mr. Wuzzat

I have no desire to know your real name and no desire to post it.

In fact this is not about you at all. It is about all the other members here frequent posters and those in the trades and those that come here seeking information with a small skill sets sometime and wishing to learn some basic knowledge in an attempt to do some work for themselves.

We need to comment and help others when we are very sure our comments and advice are in line with the direction we want the forum to give out information. We need to give information in a manner that removes as much risk as possible from the poster getting hurt following it. You are protected here as you point out no one knows who you are. When you give advice you are speaking for the forum and when your advice is not sound in the view of the experts here they waste their time correcting it and waste the OP’s time and confusion.

As example. There is never a time when we should suggest pushing two wires into an outlet to test anything. That is only the tip of the iceberg of poor reason in advice giving. My PM was making an attempt to see if you would work with us on this but it is clear you like the controversy more than helping others. For that reason you are going to be permanently banned by me with the blessing of the rest of the Mods here.

It is a shame as you have made 2474 posts so you seem to have desires to be here.
 
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