Testing Wire from Fire

[brian john]

Re: Testing Wire from Fire

Don:

I agree with your statement fully.

the fire area unless I could both physically inspect the full length of the cable and electrically

At no time did I say to do otherwise. My statementr was use common sense, know what your doing, only for questionable cables (no evidence of damage not sure if heat effected these cables). But for some reason everyone wants to avoid this statement. Either from a lack of understanding or some preconcieved notion.

 

[brian john]

Re: Testing Wire from Fire

Mis-stated NETA spec. 50 megohmsfor cables 600 voltsMaximum. B

nnie sorry I bother you. But, please explain either here or in private email.

 

[jxofaltrds]

Re: Testing Wire from Fire

This thread is getting "hot".

Mike P.

 

[roger]

Re: Testing Wire from Fire

Brian, take a minute to read flightlines post. We too have numerous meggers, data loggers, IR cameras, ground testers, medical analyzers, PQ testers etc... We offer all of the above services, our motor shop does the same along with Vibration Trending & Analysis, On Site Balancing, Laser Alignment, and Ultrasonic Surveys.

Every time we get a new toy everybody that is trained to use it and has access to it thinks it's gods gift to the industry. But we do know better, they are only tools and can be deceptive.

Roger

 

[bennie]

Re: Testing Wire from Fire

Brian: You can't bother me. I take offense when you insinuate the others, on this forum, don't know how to use test equipment.

Read their posts and you must agree there is some of the most talented trades people, in the industry, on this forum.

 

[iwire]

Re: Testing Wire from Fire

We all like cool tools but sometimes experience is a better indicator.

We where repairing an industrial electric room that had been exposed to just the heat and smoke from a fire. There was about a dozen 75 KVA 480-208/120 transformers mounted at the ceiling level.

We all wanted to replace a certain amount of them, but out came the testing equipment. I do not know the methods of the testing, but it was done by a company that specializes in testing.

To keep it short, two of the transformers that we would have replaced, tested good but later failed in a shower of sparks, one as soon as energized, another after running for a few days, shut down and when reenergized again "boom"

Commonsense said they should have been replaced judging from the heat damage around them, but a reputable testing company gave them the OK.

Most fire jobs have an insurance company trying to short change their client by not replacing everything damaged by the fire.

IMO the customer should end up with an installation that is equal or better then what they had before the fire.

I say better only because codes get changed and the replacement work must meet new code. I am not advocating cheating the insurance companies.

Bob

 

[pierre]

Re: Testing Wire from Fire

Flightline
your last post is very well written.
Bennie
Flattery is a wonderful thing, modesty isn't so bad either. No dummy are you.

I thought all electricians were known for not reading instructions I would say now that all electricians are pretty darn stubborn

Brian
I also believe in 'sticking to my guns' when I believe I am right. Not to say you are wrong, but sometimes getting past a thought that a person may be so intense about can make one say things to others that one may not really mean.
I think enough has been written here for all who have been reading to make their decision, and this thread should probably be halted before someone becomes really offended.
I will say that a lot of very good information was written by all, it was fun to follow.
One of the good things about these forums is there is a lot to learn, it may not be just electrical.

Pierre

 

[bonding jumper]

Re: Testing Wire from Fire

IWIRE

reputable testing company gave them the OK.

Where can u find one of these? Are they usually Engineers? Thanx

 

[bennie]

Re: Testing Wire from Fire

The testing experts will charge more than the cost of replacement of wiring. After the tests there will remain a lot of unknowns.

I know personally of an incident where fire damage occurred in the wiring, and was patched up. Then the patch blew out and started another fire. This time the house was totaled.

 

[brian john]

Re: Testing Wire from Fire

Gentlemen I'm not trying to be argumentive or scarey.

In my post I said one must use common sense. Testing is not in itself the magic answer.

Commonsense said they should have been replaced judging from the heat damage around them, but a reputable testing company gave them the OK.

 

[friebel]

Re: Testing Wire from Fire

To: Bonding Jumper, Yes, there is a very simple and basic test for any wiring circuit. The test is using a megger. If you are not familiar with using a megger, then you need to get a qualified electrician to do this. Basically I will assume that your wiring system is 120/240 volts single-phase. A megger will put out a DC voltage. I would test this system with 500 vdc. But again you need to understand what is the minimum reading that would still be ok in megohms to ground. If I were testing this system out with a megger at 500vdc, I would want to see a reading in the range of infinity to about 500 megohms.
If I could not get this reading, then I would probable replace the wiring.

 

[bonding jumper]

Re: Testing Wire from Fire

Wow, how did this come back again I've learned a lot since I created this post and I now am happy to have experience with megger testing. I'm also glad that I posted this a while ago because it gave me time to think about how megger testing works and when it was finially taught to me, I had pleanty of questions.