ECN Forum Forums General Topics of the Trade General Discussion Area Ground Fault Circuitry

This was most likely an arcing fault and would never pull enough current to open a breaker. The fire may have been prevented by an AFCI depending on the type of arcing that produced the heat. It sounds like a poor quaility connection on the receptacle that was producing heat when there was a load. If so this wa a series arcing fault and even an AFCI might not detect this fault. If it was an arc between the hot and grounded conductor, that would be a parallel arc, and an AFCI would have opened the circuit.

I do expert testimony and this guy sounds like a nut. There is no requirement fo put a freezer on a GFI. You would not want to do this for fear of a power outage and the freeezer defrosting. From what you have posted there must be a lot more to this that what you have said. I would like to know how it was determined that the water leaked into the outlet. Check out the freezer itself. It may be defective and caused an overload.
Also check out why the breaker did not trip.
You did not say whether the outlet box was metal or plastic. It would be more likely that an arc may have started the fire. Anyway I think your expert is nuts.

[This message has been edited by Bob (edited 03-02-2002).]

I have a question about the inspector was he an electrical expert or an expert at getting insurance companies off the hook. If what he said is right then many houses in North America are in serious trouble. I would be interested in his recommendation on how to install a box though that really could be interesting and I'd like to see him install it.

Don, I thought you disliked AFCIs?

electure,
I don't like them because they have been represented as a "cure all" for electrical fires. Notice that I stated that they may have prevented this fire if the cause was a parallel arcing fault. A GFCI breaker will also detect and clear all parallel arcing faults on any wiring system that is compliant with all editions of the NEC that require the use of an EGC in the raceway or cable. I have stated that I do believe that they will act to provide protection from parallel arcing faults, but I believe that the vast majority of electrical faults are of the series type.
Don(resqcapt19)

A GFCI would not have prevented this fire
I have witnessed this happen , it at best will trip the GFCI outlet , but remeber the power is still there ,
this GFCI got wet and it melted , it's a good thing someone was there or there would have been a bad thing .
They should get an investigator who has knowledge of this kind of thing

Wow. I never expected this. It was a metal outlet box in a manufactured home. The expert said that smaller nails should have been used to attach the box to the stud, not the 16P. We have determined already that the freezer was faulty in that it had a leak and the water somehow allegedly leaked into the outlet causing the fire. I don't know if the outlet was dedicated for the freezer. That's actually a great question. Thanks for all of your replies, they are very helpful and I'll keep you all updated on the outcome.
Alan

Highvoltage,
I said a GFCI breaker would open the circuit on a parallel arcing fault in a code compliant building wiring system. It is very nearly impossible to have a parallel arcing fault on a building wiring system that is not also a ground fault.
Don(resqcapt19)

Alan,

Unfortunately, you have been involved with an "Expert Of Bull****" [A Quack Of All Trades], in regards to this Freezer situation.

First off, as everyone has prevoiusly mentioned, GFCI protection is used to protect personnel [AKA The person(s) using an Appliance] in the event of a shock hazard posed to them from a Ground Fault situation [shock to Ground].

The only way a GFCI would be effective in the situation you are describing is if the Water leakage from the Freezer caused a high enough Ground fault current to "Leak" on the "Load" side of the GFCI device.
That may have tripped the GFCI and prevented the resulting fire.

That is only an assumption, and it leaves too many areas wide open, in which the resulting fire may have started much easier and the GFCI would not have been able to trip - even if the device was operating better than "average".

2: If the Investigating Person told me that a Metallic Outlet Box with smaller than 16d nails used for support of the Box, would have any merit in nullifying the heat transfer during a fire, I would ask the person to take a Breathalizer Test first to determine the Person's Toxicity / Blood-Alcohol level, then do a Psych. evaluation test to determine the Person's state of mind [only after verifying that the date is not 04/01/xx]


In all seriousness, the fact that the person has passed their own opinion of very questionable merit to ANYONE INVOLVED with the event sounds like a free ticket to dismissal from future investigating tasks!
[AKA Pink Paycheck w/ the word "Termination" printed on it!]

Here we have a Metallic Outlet Box, supported by 16d nails, in an enclosed wall made of combustible materials.
The Framing Members ["Studs"] will also have 16d nails driven through them; at the Top Plate, Bottom Plate, and to secure "Fire Blocks".
Many Metallic "Ties" used in Framing are also secured with 16d nails.

If the Metallic Outlet Box was the primary source for heat sinking [Conducting the heat from the fire to a cooler spot/spots], wouldn't this be more prone to set fire to the stud? [personally, I think the heat will concentrate on the box, then conduct much easier to the surrounding air way before flames begin to appear on the stud].
Also, if the nails are thin as compared to the heat sink, and they extend into a material which does not heat sink as easilly as the metallic items will, won't this RETARD THE HEAT TRANSFER [nullify it's conduction]???

Time to ask this Investigator to go back to his/her planet of origin and do Investigations there.
If returning to Earth, prior to doing Investigations again, be sure this person becomes more educated on the simple laws of Physics for this planet

Sounds like a Quack to me!

I can see the OCPD not tripping in this event, as the load current probably did not exceed 10 amperes [lucky to see that level].
This would be a really loud and scarry fault, but of very low magnitude.

This type of event would be a prime target for AFCI devices [as pointed out by others]. GFCI's and standard OCPD's would offer very little, if no protection in this situation.


[disclamer]Just My $0.02! Not verified proof, or relavent data[/disclamer]

Scott SET

Suggest you look in the phone book under electrical contractors, pick out two or three of them and have each look at the property. Ask them thier opinions in writing. They will be a lot more realistic than the paid b***s****er you currently have.