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Posted By: rj arc fault running microwave - 09/06/05 11:13 PM
What little I do know about arc fault breakers, should people try to run microwaves and refigerator? I found a acr fault breaker trip and the microwave and refigerator was on this circuit. They told me that it had been tripping out for over a week and they kept resetting the breaker. Now the breaker had to be changed out because it will no longer reset, as soon as you apply power it trips.
I told them not to run the refigerator and microwave on that circuit. I was wondering how much does it take to trip a arc fault and what should not be ran on the circuit. Any ideas of information would be great. Thanks a million
Posted By: renosteinke Re: arc fault running microwave - 09/07/05 12:50 AM
Rj, there should not be a problem.....I suspect the microwave is nearing the end of its' life, and that is what's causing the problem.
Posted By: Electric Eagle Re: arc fault running microwave - 09/07/05 01:09 AM
It shouldn't be a problem. I'd bet it's tripping due to amperage. We dedicate microve circuits around here so you put the fridge, micro, and who knows what else on it and its bound to trip.
Posted By: rj Re: arc fault running microwave - 09/07/05 01:15 AM
Ok I should of told you that the microwave pulls 9 amps the the fridge pulls 1.2 amps. So I don't think that it was tripping because of amps. being to high. The breaker gets 3 outlets in the bedroom and the only other thing pluged in was a clock and a lamp with a 60 watt lamp.
Posted By: sberry27 Re: arc fault running microwave - 09/07/05 03:09 AM
I have see problems with micros where they use the door all the time as an off/on switch. Those little door switches take a beating, have seen them arc quite violently. I have to keep telling my mother to use the stop button instead of opening the door.
Posted By: macmikeman Re: arc fault running microwave - 09/07/05 08:01 AM
quote"Ok I should of told you that the microwave pulls 9 amps the the fridge pulls 1.2 amps." What size and brand of fridge pulls 1.2 amps? That seems to be a little low to me for a fridge.
Posted By: e57 Re: arc fault running microwave - 09/07/05 08:04 AM
AFCI's have known conflicts with some types of equipment, and maybe the technology has not caught up with the micro reffer combo. What i do know is that certain types of speed controled motors, and LCD or Plasma TV's and monitors will trip them. It's due to a change in the waveform. The AFCI recongnizes this as an Arch Fault. Seeing that the reffer may be cap start, and the micro is just loaded with them, the circuit may just be doomed to be a nuissiance. So, why do you have AF's in the Kitchen? Is that a 2005 NEC thing?
Posted By: Alan Belson Re: arc fault running microwave - 09/07/05 10:54 AM
A 150W compressor should heatpump 450W on a modern machine, = 0.13 tons of refrigeration. That's plenty to chill a small insulated box. However, the starting current might be over 7 amps if the compressor starts loaded, ( there are soft start compressors on the market.)

Alan
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