?'s from Mike Holts exam prep book, NEED ANSWERS!

[tecelectric]

1. What is the feeder and servive demand for eight 6.75 kw dryers in a commercial laundromat?
a-70 kw
b-54 kw
c-35 kw
d-27 kw

2. What is the feeder and service demand load for seven commercial washing machines at 1500 VA each?
a-10500 VA
b-15000 VA
c-1125 VA
d-none of these

3. What is the feeder and service(overcurrent protection device) general lighting demand load for a 3200 sq. ft. dance club?
a-3200 VA
b-6400 VA
c-8000 VA
d-12000 VA

These questions and answers are word for word. Can you please site code articles, that you used.
Thank you!!

 

[charlie b]

Re: ?'s from Mike Holts exam prep book, NEED ANSWERS!

I think you need to take a shot at it yourself first, and give us your code citations. At the minimum, tell us what you've tried to do, what sections you've looked at without success. We're here to help, but not to do your homework for you.

[ March 24, 2003, 05:24 PM: Message edited by: charlie b ]

 

[peter]

Re: ?'s from Mike Holts exam prep book, NEED ANSWERS!

Tec--
I am currently going over Chuck's Exam Prep. Book first edition and don't seem to recall these particular questions. Perhaps you have a newer edition.
Anyway, the version I am using has answers in the back of the book along with the relevant Code citations. Be aware that there are several wrong answers and a bunch of typos in there. [When I'm finished, I'll send him a detailed message about that.]
One word of advice: some of these questions are tricky. A simple seeming question might really involve a derating factor or an expemption. One thing is that a washing machine in a residence would be on the laundry circuit so it's not counted with other appliances.
~Peter
[PS: If you look carefully on the copyright page, you will see that it is (C) Charles Michael Holt, Sr. -- hence the "Chuck".]

 

[tecelectric]

Re: ?'s from Mike Holts exam prep book, NEED ANSWERS!

charlie b:
thanks for the boost of confinedence, I dont need anybody to do my homework for me, I did do it already, and had some questions that my teacher couldnt answer, thats why I asked these questions, hoping to clear things up. I didnt put my answers down to hopefully not influence anybodys answers, but anyways, heres what I came up with:

1)54 KW
took 100% of the eight dryers, but couldnt find anything in the code to tell me to do this, thats my first question, the second is, why wouldnt the demand factors of table 220.32 be used, to me the question doesnt have enough information.

2)10500 VA
did the same thing as in question 1, but the same questions arised.

3)6400 VA
took 3200 x 2, from table 220.3(A), but my teacher got 8000 VA, because he said you have to multiply it by 125%, from 210.19(A)(1), where does it tell you or what determines if it is a contuinous load, to me you need more information in this question, but what do I know!

 

[stamcon]

Re: ?'s from Mike Holts exam prep book, NEED ANSWERS!

Tec, my take on the first two questions is that in a commercial setting, it is more likely to have all/most of the machines running at the same time. For #3, the definition of "Continuous Load" is - A load where the maximum current is expected to continue for 3 hours or more.