Mike Holt Master Exam question

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I purchased via on line a Master Electrician exam and answer sheet. OK. Now. Question 27 under Calculations asks." What is the general lighting and general use receptacle load for a 30,000 ft sq. bank?" Mulitple choice.
a)162kva b) 123kva c) 173kva and/or d)151kva.
My question, is in the answer it relays to tables 220.3(A) and table 220.13. (30,000 ft2 x 3.5va x1.25) Where do I find the 1.25 multiplier?
 
Re: Mike Holt Master Exam question

220.3(a)table use the banks for 3.5 X 30,000sqft = 105,000va X 1.25% (215.2 A 1) continous load = 131,250va. 220.3(A) also states you need 1VA per sqft for general purpose rec. so thats 30,000va, and 220.13table state you take the first 10,000va at100% then take the rest of the 20,000va at 50% = 10,000va. 10,000va (100% of the first 10,000va) + 10,000va (50% or 20,000va) =20,000va for a rec. load. now take the 131250va for general lighting + 20,000va for rec. load = 151,250 or (151kva) for the load of the bank. i think this is right. its been awhile.
 
Re: Mike Holt Master Exam question

I believe it is incorrect to derate the 30,000 va load for receptacles. In Mike Holt's Electrical Exam Preparation 2002, an example (p.389) does not derate an 18,000 va load for receptacle load for a bank. 220.13 allows derates for receptacle loads computed at not more than 180 volt-amperes per outlet in accordance with 220.3(B)(9). The 30,000 va load however was not calculated in that manner. It is an allowance for an unknown number of receptacles based on square footage of the occupancy. 220.13 is not applicable to the calculation.
 
Re: Mike Holt Master Exam question

Hey thanks to some intelligent person. I realized the continous 125% I had forgot. Thanks There will be more questions???? :eek:
 
Re: Mike Holt Master Exam question

I have found the same problem with the demand factor being used for the receptacles. In the master example the 1 va per sq. ft. has been demand factored. In the exam prep book the 1 va per sq. ft. was not demand factored but left at the full 1 va figure. I asked this question in another part of the forum. I believe if I am reading the code correctly that you DO NOT factor the receptacle load if you use the 1 va per sq. ft. method. You use the demand factor if you know the number of receptacles and they are based on 180 va or less. I am taking the WA admin test this week and would like to know which way is correct. I might to know it.

Woody
 
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