Electrical Wiring in the Home/Circuit Breaker


Something happened this morning that has me worried. I have a small space heater on the floor of my car that's connected to a timer which is plugged into a bar cord in the garage. I plug it in at night and the timer goes off a few hours before I leave for work. The heater is pointed upward and it's reasonably safe to use. However, this morning I did it differently and plugged it in after I started my car. The temp was -21 and the cord was very stiff. I think when I slammed the car door on the stiff cord it broke the insulation. When I picked it up to unplug it the sparks flew and burned the cord in half. What worries me is, it didn't kick a breaker. Shouldn't the breaker kick when there's a short like that? The bar cord didn't kick either so I wonder if the timer might have fried and closed the circuit instead of the breaker? Is there a possibility that the breaker malfunctioned and maybe I should replace it? Thanks Bob!! Steve


Sometimes the duration and intensity of a short circuit may not be enough to trip the breaker. This is where "arc fault" breakers come in. This breaker is designed to "see" faults like yours as a problem and trip the breaker. It sense's the erratic sparking and trips the breaker. While a regular brerak will not do this unless enough current passes by the breaker long enough to trip it.

If you would feel better about changing the breaker to dispel any doubts about wether its defective or not you can certainly do that but I beleive thats why the breaker did not trip.

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Electrical Wiring in the Home

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Licensed Master Electrician (32 years) 6165B Contractor in Closter New Jersey with 40 years total experience in Residential - Commercial - Industrial work. Emergency Service - General trouble shooting and repair work - ONAN & GENERAC generator installation - Paddle fans - Kitchen & Bath exhaust fans - AC lines - Smoke detectors - Telephone lines - Cable TV lines - Computer network cabling - Exterior lighting - Recessed lighting - Security lighting - (200 - 150 - 100 amp service up grades) - Electric Heat - New circuits - New appliance hook ups - and more ! FREE ESTIMATES 201-358-1552 Fully Insured


Licensed contractor in Closter New Jersey.

"The Frank Williams School of Electrical Construction". My dear old boss is 100 ! and still going God Bless him. I started working for "Tenafly Electric" right out of high school at 19. He was tough but I learned more working for him in 8 and half years than most guys. We did mostly industrial work while doing some commercial and residential so I was fortunate to be exposed to all 3 areas of electrical construction. The guys I worked with were all good guys and I stay in touch with some of them still. Most of us went into our own buisness's which says something about the caliber of the guys I worked with. We had some interesting clients : Wella Corp. of shampoo fame, Farah Fawcett etc, I didn't buy shampoo for 10 years. It was a great place to work. Pan Am the former airline just before they went under, another great place to work, nice clean environment. C&C Metals, the largest button manufacturer in the US at that time, a not so clean environment but a very interesting place to work, lots of machine's cranking out buttons of all kinds but you had to be on your toes, it was a potentially dangerous place to be . All kinds of action going on around you.

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