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Yep. The correct person to ask about electricity is a Physicist, or in your analogy's case, a lawyer.


As a physicist*, I would suggest speaking to an electrical engineer.


As an EE, I say ask one specific branch of the Electrical Engineering profession.

see [1], here there are 3 specific sub disciplines you can test in, and all are considered "EE"

computer

electronics

power

you want to talk to an expert in the power arena, but from what I remember when studying for the exam, the content was mostly things way above residential (which is what this discussion has been about) and more of power gen and conversion. Y, delta configurations and conversions, power angles and factors, etc. the kind of thing you come out really knowlegable in one very small area and still clueless on the NEMA power plug.

[1] http://www.pels.ca.gov/applicants/refs.shtml


But, conversely, be careful about asking a physicist to wire your home. They may not be conversant with the codes, which contain a lot of practical wisdom.

I once tried to convince a physicist friend to not use just solder on his ground connections. He thought that by using solder he was going above-and-beyond the code.

But actually, ground connections are required to be pressure-fit, not just soldered, to ensure that heating during a current spike does not allow the connection to separate.


Sorry, but that's not true. For your solder joint to fail it would have to be hot enough to cause a fire.

Pressure type connectors are simply cheaper and easier, and were not initially allowed because soldered connections are better.

http://www.justanswer.com/electrical/18vcb-not-allowed-solde...

Soldered (sweated) fittings are not allowed on gas lines for this reason though: If there was a fire you don't want the gas lines to leak after the solder melts.


What I said is correct according to the NEC. In fact, the relevant part of your link says:

"Soldered splices shall first be spliced or joined so as to be mechanically and electrically secure without solder and then be soldered."

So, the joint has to be totally secure, mechanically and electrically, without the solder.

My friend was relying on solder and tape, with an inadequate mechanical connection that relied partly on the solder to hold it together. His installation was therefore not compliant with the NEC, although he did not want to admit it.

If you read the explanatory note related to the code, it gives the rationale I gave. Maybe it's BS, but it's the NEC.


> relied partly on the solder to hold it together

You are not ever supposed to do that. I was assuming he wrapped the wires together securely first. http://en.wikipedia.org/wiki/Western_Union_splice or even http://en.wikipedia.org/wiki/Rat-tail_splice

I was just saying you don't have to use a pressure type connector - you can use a wrap splice, then solder it. (Electrical tape is not sufficient insulation, but you said this was a ground.)


The NEC is even more restrictive with equipment grounding conductors, actually. You are not allowed to use solder-only connections on grounds. I don't want to go farther down the road, since we're only talking to each other, but here is a link FYI:

http://www.ecmag.com/?articleID=8721&fa=article

The relevant part is:

"Connection of Grounding and Bonding Equipment. Grounding conductors and bonding jumpers shall be connected by exothermic welding, listed pressure connectors, listed clamps, or other listed means. Connection devices or fittings that depend solely on solder shall not be used."

You really cannot just twist-and-solder for a ground. It is specifically forbidden by the NEC.




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