Stuff Electricians Should Know!

So why would this need to be put in the NEC?

Let’s just get into a little electrical theory for a minute.

When alternating current (ac) flows through a conductor, a magnetic field is created around that conductor which is constantly expanding and contracting with the amplitude of the current.

You know that the amplitude in the US is at a frequency of 60 cycles per second or 60 Hz.

Now, since Alternating Current reverses polarity 120 times per second, it stands to reason that the magnetic field also reverses its direction….. 120 times per second.

So why does that matter? Simple, the expanding and collapsing of the magnetic field induces something called eddy currents in the ferrous metal parts that surround the conductors.

In todays episode we answer a question from Mike. He asks:

"I had a commercial job where the plans state 200 amp 3 phase 120/208-4wire exterior surface mount panel with 200 amp main breaker. I was told by 2 electrical companies that i needed a panel board (which was $750) and by 1 electrical comapny i can use a basic loadcenter ($280) which is correct?"

Today I  just wanted to bring you a couple of items to remember when doing a wire pull. There are four  major  things to remember:

1-Pull Evaluation

2- Conduit Proofing

3- Conduit entry and Exit

4- Lube