I just received a set of plans with the following specifications:

-"At the time of the final electrical close out, and in the presence of the general contractor, architect, or owner, the electrician shall apply a minimum load of 3 amps to the distal end of each electrical circuit. The home shall be inspected under load using a gauss meter. Any elevated magnetic fields greater than .5 miligauss will indicate the presense of a code violation or that wiring has been damaged during the construction."

And that is just one of the "interesting" specs.

Thoughts, Comments?

Thanks

Highground

I will be curious about how and more importantly where they measure this.

I'm not sure how that indicates a code violation or damage to wiring, but EMF levels above 4mG are suspected to cause leukemia.

You'd measure it by walking around the house with a probe. Strongest levels would be near the wiring.

I suppose it could indicate that you have leakage current or a multigrounded neutral, as the currenet in the hot conductors and neutral will always be opposite and the subsequent magnetic fields almost perfectly cancel each other out... Just don't use a hairdryer as your load- they put out something like 300 milligauss at 6'!

It could mean nothing, I take lots of contracts with silly crap like that in it and nothing ever comes from it… but there have been a few memorable times when the goofy engineer who wrote that crap showed up to follow through, or even worse some over zealous GC felt like he had to enforce every last letter of the specs when the engineer and owner were happy with the project.

My feeling is, that is this is a “green house” project and there is a real potential that you may have to go through this test should you get the project, then make sure there is enough money in your proposal to cover the headache.

On a side note I was not aware that NEC says this, it sounds like some egg head made it up:

We see even goofier reqiurements in voice/data cable installations where "consultants" or IT people write the specs. We know that the customer is being sold a bill of goods with gross overkill to address future capacity. These guys have customers spending 3-4 times what the job should really cost by demanding printed test results, 30 year warranty, on and on and on. No customer is going to stay in the same spot for 30 years and even if they did, technology is growing/changing at such a rapid pace that the overkill the customer paid for is obsolete within 7-10 years.

I would first say that the specification as written cannot be met.

1) The Earth's magnetic field at the surface is on the order of 300 - 600 milligauss. Kind of blows away the 0.5 milligauss maximum. Of course, the specification should really differentiate DC magnetic fields and AC magnetic fields.

2) Conductors carrying current always create a magnetic field. In a properly wired electrical system, the balanced current flow between adjacent circuit conductors will mean that this magnetic field falls off very quickly. But in the space _between_ the conductors the 0.5 milligauss threshold will be exceeded. There is no specification for the locations to be surveyed, and no exclusion of the wires themselves.

3) There is no differentiation between magnetic flux caused by your wiring and magnetic flux caused by other systems. You don't want to be on the hook for flux caused by current that you don't control. If the flux is present with your circuits off, you shouldn't be on the hook for fixing it.

4) I would want to see a baseline survey as well as a survey after all building steel and grounding electrodes were placed.

5) While you should be on the hook to correct your wiring defects (eg. crossed neutrals, neutral-ground faults, etc) you shouldn't be on the hook to pay for the magnetic survey time to find these defects.

-Jon

Charge 'em! And charge 'em good!

When you quote the job, price it out as you normally would, then itemize each of the silly tests, specifications, and other nonsense, and watch how quickly those items get dropped from the plans. If they don't get dropped, at least you know the client you're dealing with has more dollars than sense.

Joe

30-Year warranty!?!?!?!

Holy Cow! I don't believe data will even be using copper in 30 years. Hell, I don't believe data will be on copper in 10 years.

I have been hearing about the death of copper for 20 years. I bet it will ber around longer that I will.

Copper's been here too long in the data field, it's here to stay.

Fiber to the development, copper to and in the houses.

Ian A.

Highground, throw all referance to the job, and GC into the rectangular file - or mark up the bid 1000%.

Steve, do you have any evidence of that? What I remember is that there was a huge study in, IIRC, Sweden, that compared proximity to power lines with a large number of maladies, and this study showed a slight elevation in leukemia. HOWEVER... When you are measuring as many things as they measured, you will, by random chance, get some things that show up above average, and some that show up below average. That was the conclusion about what happened in that case--there was a rather small number of leukemia cases, and by random chance there was a slight clustering around power lines. When researchers went looking for this in other locations, they found no correlaton between power lines and leukemia in other places.

That doesn't stop the alarmists from proclaiming that it has been proven that power lines cause leukemia, and shouldn't be built.

This is from a while back. Perhaps you have more up-to-date information than I do?

All I know is what I gathered from a quick google search. I'm sure there are conflicting studies out there.

This sounds like they wrote a loophole into the spec so that they can get away without paying you, even if you try a lien or court case.

RUN AWAY !!!!!!

You could always bid the job and exclude this test from your scope.

Some of the other interesting specs include:

There is to be an exhaust fan in the garage that runs for twenty minutes after the the garage door opens or closes.

And there are to be switches outside each bedroom to kill the power to the entire bedroom before they retire for the evening. Besides the smoke detectors, does anybody see any code problems with that one?

Thanks
highground

I see a problem with the alarm clock, and running out into the hall naked to turn the lights on, but there's no Code against silliness.

I had a friend that wanted something similar to this when he wanted to keep his kids off the video games and such while grounded... He also wanted keyed switches

That sounds like someone who is far enough off the deep end that I wouldn't want to do business with them. (The term "paranoid schizophrenic" comes to mind, but there is nowhere near enough information here to make a reasonable determination.)

Seems I had job like this for a short time for the 'tin foil hat' set. (EMF-a-phobes) We only did the foundation work, by which time the GC and subsequently the company I worked for were released from contract. These people wanted all cabling routed away from sleeping areas yet still wanted bed-side outlets for the cordless phone, cell phone charger and what have you.

People like that have been reading too many poorly written articles by people with 'greener than thou' political agendas who regurgitate data that they either have little understanding of, or just made up entirely. And there seems to be an epidemic of it in certain circles of people... Whats worse is that you can't seem to debunk the crap they have been fed without seeming anti-green. At which point they dont trust anything you have to say anyway. But that could be an advantage if you feel unscrupulous. I was on another job recently where there was a lot of talk about the required (Contractualy) use of recycled lumber. The entire job used no dimensional lumber at all. (*except all the concrete forms... ) They used all engineered lumber through-out the building under the guise that it contained 'some' recycled wood. Little do they know that they grind entire trees that they wouldn't cut anyway due to visual, staightness or other defects for the other 98%. But to them it contains some recycled wood, and they are willing to pay top dollar for that green grin in the end.

Some folks just refuse to believe that they're not getting out of this life alive...

Ok I think I was wrong. Yes you could write one hell of a scope letter to try and protect yourself form these folks, but you just can’t excluded dealing with retarded people from your proposal.

Why not run it in RMC and FS boxes?

Just searched the 2005 Code and the 2005 Code Handbook (got 'em on CD).

No reference to "magnetic fields".

I agree with JJM above - write up a test proceedure, itemize the cost(s), and watch it vanish...

Grov

I would run it back the engineer or architect and make them design the electrical system, as to type of wire and placement of all conductors and make them write the test specs. It sounds like you could be come trapped by this if you do it yourself.