Ky Testing Help Me

[TDCHUNT]

3 Phase 480v Delta Sys. Is Balanced With 30 Kva Load Per Phase What Is The Line Current In Amps Giving An Actual 8000 Va Total Load? Where In The Nec Code Book Can I Find This

 

[BackInTheHabit]

3 Phase 480v Delta Sys. Is Balanced With 30 Kva Load Per Phase What Is The Line Current In Amps Giving An Actual 8000 Va Total Load? Where In The Nec Code Book Can I Find This

Phase Amps X 1.732 = Line Amps
Line Amps/1.732 = Phase Amps
Phase Volts = Line Volts

If you have actual load of 8000va (8000va X 1.732 = 13,856va)

I'm not sure there is an actual Code Reference, just electricians math. I had to look it up myself.

I'm sure more math adept users of the forum might be able to elaborate.I please correct me if I'm wrong.

 

[bob]

3 Phase 480v Delta Sys. Is Balanced With 30 Kva Load Per Phase What Is The Line Current In Amps Giving An Actual 8000 Va Total Load? Where In The Nec Code Book Can I Find This

TD
Check those numbers again. You show a load(connected I assume) of
30000 va(30 kva) and you want that amps for 8000 va. Is that 8000 va per
phase or 8000 total?

 

[TDCHUNT]

This Doen't MATCH The Anwser Choices I Have A.)62.5 B.)96.22 C.)108.25d.)166.66 This Is On The Ky. Journeyman Test That I Have Failed Twice. I Am 99% Sure I Wrote It Down Right

 

[BackInTheHabit]

This Doen't MATCH The Anwser Choices I Have A.)62.5 B.)96.22 C.)108.25d.)166.66 This Is On The Ky. Journeyman Test That I Have Failed Twice. I Am 99% Sure I Wrote It Down Right

How did you come about to taking the test?

Vocational school?

Four years minimum of work under a licensed electrician?

Who administers the test?

 

[TDCHUNT]

Phase Amps X 1.732 = Line Amps
Line Amps/1.732 = Phase Amps
Phase Volts = Line Volts

If you have actual load of 8000va (8000va X 1.732 = 13,856va)

I'm not sure there is an actual Code Reference, just electricians math. I had to look it up myself.

I'm sure more math adept users of the forum might be able to elaborate.I please correct me if I'm wrong.

THIS DOES'T MATCH THE TEST ANWSERS ON THE KY JOURNEYMAN TEST THAT I HAVE FAILED TWICE ANWSERS A.)62.5 B.)96.22 C.)108.25 D.)166.66

 

[TDCHUNT]

4 Yrs Exp Lazer Grade Testing

 

[BackInTheHabit]

Haven't tried these formulas yet myself, but try this Mike Holt Link on Delta Transformer Calculations.


http://www.mikeholt.com/mojonewsarchive/EC-HTML/HTML/DeltaTransformerCalculations~20030915.htm

 

[BackInTheHabit]

THIS DOES'T MATCH THE TEST ANWSERS ON THE KY JOURNEYMAN TEST THAT I HAVE FAILED TWICE ANWSERS A.)62.5 B.)96.22 C.)108.25 D.)166.66

My Answer: C) 108.25 (closest answer):grin:

To determine Amperes when KVA and volts are known:

3 Phase KVA x 1000 / Volts x 1.73

Found it HERE.

 

[nakulak]

amps = kva/(voltage x 1.73)
= 8000/(480 x 1.73)
=9.63

(did I read 8000 and should be 80000 ? off by factor of 10)

 

[Chenley]

Remember that you can write ANYTHING in your codebook as long is it is written in ink. I ended up having quite a few equations written in the inside cover of mine when I took the test last year.

 

[BackInTheHabit]

Remember that you can write ANYTHING in your codebook as long is it is written in ink. I ended up having quite a few equations written in the inside cover of mine when I took the test last year.

Took my tests, 15 years ago, with Tom Henry's Codebook with all the inserts. No problem using it while taking the exam.

 

[SiddMartin]

you need a 70% to pass? don't sweat this question, get the other ones right..... I know, easier said then done.