Breaker tripping problem......

[Mike Langford]

I've got an electrical problem I hope you guys can help me with.....

I've got only one 220 breaker in my 200 amp panel, that I have only my 3 hp cabinet saw plugged in to. (before I took up woodworking I used the 220 outlet for a mig welder)

About 2 months ago (usually after a thunderstorm...although at the time I didn't relate the two occurrences) I would go to use my saw and nothing would happen.....So I would check the panel box and the 220 breaker (and one of the 15A 110 breakers) would be tripped!

At first I didn't think to much about it, thinking that maybe lighting probably tipped it and it wouldn't happen again.....

But here lately since it's been raining everyday/afternoon :mad:.....without fail everytime I go to use my saw the breaker(s) would be tripped.

Any ideal what is causing this?

I think the 15A 110 circuit is for two fluorescent shop lights over a corner workbench (Which I hardly ever turn on!)

Anyone else ever have problem like this?.......... help! :(

TIA

[Bruce Wrenn]

I would carefully inspect the wire from breaker to saw for damage. Last week, my sister had similar thing happen during a storm. This week, breaker to well pump kept kicking out. With breaker in the off position, I ran my hand along wires to pump. Sure enough there was a tiny spot where the insulation was damaged. Cut out that section, spliced wires. Breaker no longer tripped, but only had voltage on one side (it is a 220 breaker). Replaced breaker and everything was fine.

[Mike Langford]

Thanks for the reply Bruce!

Although I haven't inspected my saw chord yet, I believe your sister's breaker would trip when the pump would try to kick on....because of the break (short) you found?

My breaker trips when the saw is off......Lets say I use my saw on Monday with no problems....I don't go in the shop Tuesday.....I don't go in the shop Wednesday (but it storms Wed. night and trips the breakers?)....I don't use the shop Thursday.....but when I'm in my shop on Friday and I need to make a cut on the saw......nothing!! 'cause the breaker tripped on Wednesday!.......

Why do the storms make the breakers trip?

Are the breakers bad and trip because of a slight surge in the panel? (caused by the storm?)


:confused: :confused: :confused:
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[Andy Bardowell]

Mike make absolutely sure that there is no short on either circuit that is causing this. Assuming there isn't a short it may be a loose connection, tighten all connections as tight as you can without stripping the screw head and tighten all marettes until the wires actually twist around. A loose connection will trip breakers especially 220s. By the way wrap the back of the receptacle covering the screws as you have it apart, a good practice that I learned from an electrician; each wrap insulates to 600 volts.

[Bruce Wrenn]

Mike, the breaker would trip when activated. Pressure switch, located at well controls the pump. Wire to well is "hot" all the time. Lightening surge burned thru insulation, allowing for contact with ground wire.

[Charles Lent]

Mike,

It's a bit odd that both breakers frequently trip at the same time. I think that you should check (with the two breakers off) the wiring of these two circuits to see if there is any place where the wires of both touch each other. The problem is most likely there. Don't forget to check inside of the breaker box for possible connection between them too. Are the breakers located next to each other? One may be heating up and causing the other to also heat up.
If you don't find anything, then try unplugging your saw and see if the breaker trips on it's own without a load connected. They may be defective breakers, but I don't think so. It's much more likely that there's something else causing it.

Charley

[Thomas Syrotchen]

A breaker tripping with the device in the off position is likely bad wiring creating a short before the switch in the device or perhaps the breaker has gone bad. Based on what you described, I would remove power from the circuit, disconnect the wiring from the breaker to the switch, make sure the switch is off and check contuinity between the leads and to ground. You'll likely find a short. If you do find a short in the leads, disconnect the leads at the switch and retest, should help you isolate the issue to the leads. If you don't find a short, I'd leave the saw disconnected and see if the problem appears with no load connected, if the breaker trips its likely a bad breaker.

[Lee Schierer]

Pull all three "hot" wires out of the breakers. First, check each wire to ground for any stray voltage, tehn with you Ohmn-meter check for continuity between the three wires. If you get any sign of continuity other than open circuit, you have a short in the wires.

[Prashun Patel]

Gotta be a short somewhere.
My guess is that it's coincidental that it doesn't trip when the saw's powered.

Does your 220v circuit share any receptacle boxes with other circuits - like the switch for the lights?

[AL Ursich]

I would look at the wiring between the circuit box and the saw. Could be a staple holding the wire had pinched a hot lead and is leaking to ground through the wood and the more moisture the faster it trips.

Does the saw have any old rotted wire to the on off switch?

OR you could just have a bad breaker...

A Electrician might have a suggestion.

AL

[James A. Wolfe]

Let me see if I have this straight:


A breaker trips after it rains...
Another, unrelated breaker trips after it rains...
There is no problem until after it rains...

I think I see a pattern developing here.
It is likely water getting into the panel, a junction box somewhere or damaged insulation. TURN THE TWO BREAKERS OFF. Follow the wiring from each to find where they come together. This could be a junction box, the panel or under a staple. If they run inside conduit, that could be the trouble spot. A broken wire will not cause the breaker to open. Damaged insulation allowing the current to flow to ground or to the other leg of your electrical service will cause it to open. Is this a basement shop? Is the affected breaker a GFCI or AFCI type? They are particularly touchy about moisture.
Good luck,
Jim