Another test question

[JamesJohnston]

Test question in the commercial plans examiner was:
3 roof top compressors: 27.4FLA, 27.4FLA, 24.6FLA
What is the load on the neutral?

The four answers were: 10, 50, 80, 150

Does anyone know hoe to answer this one?

 

[GoldDigger]

Not enough information given about the circuit. Are the individual compressors all single phase, on different lines?

 

[JamesJohnston]

Not enough information given about the circuit. Are the individual compressors all single phase, on different lines?

This was the only information given

 

[synchro]

The four answers were: 10, 50, 80, 150

Can't they come up with new answers? Those are the same ones as in your previous question.

 

[GoldDigger]

Can't they come up with new answers? Those are the same ones as in your previous question.

I took a test once where all the answers were the same. Either a, b, c, d, or e for all of them.

 

[drcampbell]

If the compressor motors are 3-phase, the neutral current will be zero.
If the compressor motors are 240-volt single-phase, the neutral current will be zero.
If the compressor motors are 120-volt single-phase, somebody really needs to re-think their approach.
The question is flawed and each of the four multiple choices is wrong.

 

[ptonsparky]

I've yet to see 120v roof top units but there is still tomorrow.

 

[JamesJohnston]

Not enough information given about the circuit. Are the individual compressors all single phase, on different lines?

If the compressor motors are 3-phase, the neutral current will be zero.
If the compressor motors are 240-volt single-phase, the neutral current will be zero.
If the compressor motors are 120-volt single-phase, somebody really needs to re-think their approach.
The question is flawed and each of the four multiple choices is wrong.

Thank you, your answers are the same that I am getting from others.

 

[Tulsa Electrician]

Test question in the commercial plans examiner was:
3 roof top compressors: 27.4FLA, 27.4FLA, 24.6FLA
What is the load on the neutral?

The four answers were: 10, 50, 80, 150

Does anyone know hoe to answer this one?

That's just plain nuts. Based on the answers, sure this not a common factor question. 1,2,5&10 with
prime factors of 2 and 5 and a GPF of 10.
The NEC in 220 using round up or down rule I would find the ansawer based on GPF of 25 and 27. This is 1. So I go with A.
That's makes about as much since as the question and would be my written answer back to them.
After all it's Turkey day .

 

[ptonsparky]

That's just plain nuts. Based on the answers, sure this not a common factor question. 1,2,5&10 with
prime factors of 2 and 5 and a GPF of 10.
The NEC in 220 using round up or down rule I would find the ansawer based on GPF of 25 and 27. This is 1. So I go with A.
That's makes about as much since as the question and would be my written answer back to them.
After all it's Turkey day .

Well, that answer is just as clear as the question. Good job!

 

[JamesJohnston]

That's just plain nuts. Based on the answers, sure this not a common factor question. 1,2,5&10 with
prime factors of 2 and 5 and a GPF of 10.
The NEC in 220 using round up or down rule I would find the ansawer based on GPF of 25 and 27. This is 1. So I go with A.
That's makes about as much since as the question and would be my written answer back to them.
After all it's Turkey day .

Yes, just plain nuts