1 - 6 of 6 Posts

#### Jojo1226

· Registered
Residential, commercial
Joined
·
7 Posts
Discussion Starter · ·
so on my JW test i got a question like this:
a three phase circuit is 208v and a resistance of 14.2. what is the amperage?

what formula does one use to find this?? i have not found any answers on google

#### batwing44

· Registered
Joined
·
114 Posts
so on my JW test i got a question like this:
a three phase circuit is 208v and a resistance of 14.2. what is the amperage?

what formula does one use to find this?? i have not found any answers on google
Ohms law?

#### CAUSA

· Registered
Sub transient reactance X”d worshiper.
Joined
·
727 Posts
Was the question really with that wordingWith that limited information for 3 phase?

There should be some assumptions if it is.
PF is 1.
Delta or Wye does matter. The branch of a delta or the phase section of a delta current.
The other assumption is , it is a balanced system?

Links from a internet search.

So the real question is. Do you have the concepts of the phase angle of a circle?

This will help. Concepts first, then try the calculations.

There is the some math resources. I do not know your level so do not take to heart any insult with the posts.

The real Question you should be asking yourself. How much points is it worth to my over all test?

I would move on and answer all the ones I know.

Concentrate on concepts, the math will come later.

If you have more wording on the question it would help.

#### kb1jb1

· Registered
Electrical contractor 37 years. Electrical inspector 2 years
Joined
·
4,373 Posts
Assuming 14.2 ohms per phase

14.6 amps or 8.5 amps or am I wrong with both?
5.2 kw

Now I have to go back to my Henery book.

#### Jojo1226

· Registered
Residential, commercial
Joined
·
7 Posts
Discussion Starter · ·
Was the question really with that wordingWith that limited information for 3 phase?

There should be some assumptions if it is.
PF is 1.
Delta or Wye does matter. The branch of a delta or the phase section of a delta current.
The other assumption is , it is a balanced system?

Links from a internet search.

So the real question is. Do you have the concepts of the phase angle of a circle?

This will help. Concepts first, then try the calculations.

There is the some math resources. I do not know your level so do not take to heart any insult with the posts.

The real Question you should be asking yourself. How much points is it worth to my over all test?

I would move on and answer all the ones I know.

Concentrate on concepts, the math will come later.

If you have more wording on the question it would help.
ya i fell you i did skip but felt stupid that i had no idea how to do it

#### CAUSA

· Registered
Sub transient reactance X”d worshiper.
Joined
·
727 Posts
ya i fell you i did skip but felt stupid that i had no idea how to do it
That’s ok, now you know what you have to do to make this your strength.

Trick, on test. Note key words and work the problem from there. Some questions are loaded.

Make the 3phase calculations your strength. Make your weakness in to strength and keep moving forward.

1 - 6 of 6 Posts