I apologize for my lapse in replying. I have been traveling and attending to my more than full-time job!
I will try to take a few moments to answer some questions. For some of the more technical questions, I am going to our design engineers, and at this time of year many folks are taking needed breaks.
For ElectricAL:
The AFCI continually monitors the voltage. We monitor the voltage trace waveform across the resistive element in the breaker. We monitor the voltage drop and convert to current. We are looking for the spikes in this waveform that are indicative of arcing faults. When we see that there is evidence of an arcing fault of 50A RMS or greater, we analyze the current waveform for the signature of an arcing fault. If we see this, the breaker is "armed". We then look for 8 arcing half cycles over the next 1/2 second, (these do not have to be consecutive half-cycles, and they can be positive or negative. If we see 8 half cycles of arcing, we trip the breaker. If the electronics does not see 8 arcing half cycles in that time, the breaker is no longer armed, and goes through the process again. All of this is done with a custom analog integrated circuit. Additionally, we monitor arcs to ground for the parallel arcs in NM-B cable at a 30-mA level. There are MOV's on the board to protect from surges. Hope I've answered your questions.
For Motor-T and Sparky:
Smoke detectors would be covered by the changes made to 210-12 for the 2002 code that changed the word "receptacles" to "outlets".
For pauluk:
We are beginning discussions to export the technology to Europe in the IEC breakers. There is a problem in Europe that the appliances are more flammable over there due to the fact that Euro manufacturers do not use as many fire-resistant chemicals in their plastics due to concern over the environment. Someone earlier stated that they do AFCI in Europe. That is a misstatement. European standards use earth leakage, which is not AFCI.
For nesparky:
First, I apologize for your difficulties. I would like for you to email me directly at BrendanAFoley@eaton.com with your location, and the distributor and sales office that you were dealing with. I need to let them know that they are not following our "no-quibble" warranty process. In the same email, I'd like you to send your name and address so I can have the Cutler-Hammer sales engineer get in contact with you.
You did not provide a lot of details about your problems, whether the five breakers were all replacements on the same circuit or not. If you email me directly, I can go through this in more detail. I cannot be sure until we talk further, but I would suspect one of three things was causing the circuit breakers to trip:
1) There was ground current in the circuit. This could be because there was a grounded neutral somewhere in the circuit.
2) There was a shared neutral in the circuit.
3) There was arcing in the hair dryer.
The vast majority of the "defective" GFI breakers that we receive back have no problem whatsoever. We test the devices, and they test within design parameters…that is, they are functioning properly.
To all, I will try to do a better job of replying in a more timely fashion. I know that you have concerns, and I will try to address them.
Happy Holidays,
Brendan Foley
