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JPajak
Breaker trips - not under load

A 15A circuit contains only a central vac unit, and an exterior floodlight and outlet. This breaker is tripping several times a week...always when nothing on the circuit is running or turned on. I replaced the breaker - no luck. The exterior junction boxes are dry. This began occurring suddenly 2 weeks ago, and had never occurred before. There has been no work to this circuit recently. I'm stumped, and would really appreciate any ideas. Thanks.

JLMCDANIEL
Re: Breaker trips - not under load

It could be a nick in the cable that is shorting out, a nail through the cable, a bad GCFI outlet, a bad sensor on the flood if it is automatic, or something in the central vac causing the problem.
Jack

Blue RidgeParkway
Re: Breaker trips - not under load

anything plugged into but not on at the solitary outlet?

first thing I'd check is that outlet, if it is fed-through I'd pigtail it, if it is backstabbed, I'd change it over to use the screw terminals, check the ground and tape over the connections. for the few dollars it cost I'd even replace it even if it had good spring and no obvious cracks. then go from there.

does this multi-purpose circuit have arc fault protection? seems strange to have central vac and outdoor light and receptical (indoors or outdoors - wet, damp or dry location?) all on the same breaker, was the flood light a prior extention to the original circuit?

JPajak
Re: Breaker trips - not under load

There's nothing plugged into the exterior outlet. It is wired directly to the screws, and the end of the line for that circuit. Good idea though, I'll replace it and tape it up.

I added the flood and exterior outlet to an existing circuit - so not GFI protected.

Thanks for the suggestions.

Blue RidgeParkway
Re: Breaker trips - not under load
JPajak wrote:

A 15A circuit contains only a central vac unit, and an exterior floodlight and outlet. This breaker is tripping several times a week...always when nothing on the circuit is running or turned on. I replaced the breaker - no luck. The exterior junction boxes are dry. This began occurring suddenly 2 weeks ago, and had never occurred before. There has been no work to this circuit recently. I'm stumped, and would really appreciate any ideas. Thanks.

JPajak wrote:

There's nothing plugged into the exterior outlet. It is wired directly to the screws, and the end of the line for that circuit. Good idea though, I'll replace it and tape it up.

I added the flood and exterior outlet to an existing circuit - so not GFI protected.

Thanks for the suggestions.

dry location only wiring tapped into to extend prior dedicated circuit to multi-use and exterior wiring and an exterior outlet not GFCI protected prob not packed and prob not covered.

i only familiar with central vac systems that require dedicated 15 or 20 amp circuits to the power unit. some use turbine (air) driven attachments or corded attachments that plug into regular nearby outlets for power drive most use combo hoses that have pins to power from the vac attachment either line or low voltage. if you tapped into the vac system wiring that would be horribly wrong no matter what. some use low voltage switch wiring for suction control to.

moisture condensation damp location cooling outside temps might be equaling fault or arc conditions you just seeing now.

no gfci for exterior receptacle that you diy'd and tapping into required dedicated circuit = unqualified work and wrong dangerous material choices. keep circuit breaker off and call a professional to correct work and restore the original dedicated circuit.

JPajak
Re: Breaker trips - not under load

The Vac system does not need to be on a dedicated line. The external outlet is covered, but condensation is a possibility. I can handle the repairs.

JLMCDANIEL
Re: Breaker trips - not under load

Random tripping with no load sounds like a bear wire touching due to vibration, perhaps when a door is slammed or foot traffic in a certain area. That could be a wire penetrated by a nail or nicked insulation in a junction box. A faulty or loose power supply if you have one for low voltage wiring for the central vac could also be the cause. If you have a motion detector on the flood the trips may correspond to it being set off by foot traffic or animals in yard. Motion detector may be a fault.
Jack

JPajak
Re: Breaker trips - not under load
JLMCDANIEL wrote:

Random tripping with no load sounds like a bear wire touching due to vibration, perhaps when a door is slammed or foot traffic in a certain area. That could be a wire penetrated by a nail or nicked insulation in a junction box. A faulty or loose power supply if you have one for low voltage wiring for the central vac could also be the cause. If you have a motion detector on the flood the trips may correspond to it being set off by foot traffic or animals in yard. Motion detector may be a fault.
Jack

Hey Jack - thanks for the advice. I did replace the exterior outlet and found some condensation in there. If this trips again I'll check out the low voltage connections on the vac. There is no motion detector on the flood. Thanks again

bsum1
Re: Breaker trips - not under load

Our central vac has the low volt supply inside the unit. I believe it's 24 volts AC which is probably a step down transformer.
If the breaker continues to trip try unplugging the central vac to eliminate that or it might reveal that's the culprit.

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