Wa Admin 01 Test... Help needed

traderx · Mar 17, 2005

Hello all? I am to take the Washington State 01 test? I have taken the test before, but was not able to pass the calculations part and could use some help as to how to do them the correct way?. I have below some of the questions that were asked on my first time, and could use some help as to the steps used and articles that are referred to so that I can use them as a reference and be able to do on my own. Thank you to all that reply.

Question #1
Given: A multi dwelling has 4 units with 1,800 sp ft each. Building has no common area loads and none of the units contain laundry facilities.
Each unit has:
13Kva Range
1.2Kva dishwasher
.6Kwa disposer
120V compacter 12A
120V A/C 18A
2.5 Kva 240V heater

Answers:
1: 240
2: 250
3: 258
4: 269

=============================================
Question #2
Given: 120V/240V 3 wire service multi dwelling has 13 units with 1,700 sq. ft.
Each unit has:
12Kva Range
1.5Kva dishwasher
.6Kva disposer
120V A/C at 23A
2.5Kva 240V heater

Don not consider house and laundry
Use optional

Answers:
1: 610
2: 625
3: 640
4: 655

=============================================
Question #3
Given: 240V 3 phase delta system, one 15hp 3 phase motor, two 10hp 3 phase motor, one 50hp 3 phase motor. The 50hp is rated for 5 minutes interval only

Size feeder with inverse time CB

Answers:
1: 300
2: 350
3: 400
4: 450

=============================================
Question #4
Given: Duplex 120V/240V 1 phase service each 1,900sq ft
9Kw Range
5A disposal
11A dishwasher
3Kw hot water
20Kw heater
3-21A 240V A/C

Using Standard in Amps

Answers:
1: 256
2: 282
3: 299
4: 321

[ March 17, 2005, 03:46 PM: Message edited by: traderx ]

charlie b · Mar 17, 2005

Re: Wa Admin 01 Test... Help needed

The common practice of this Forum is that you should work out a solution on your own, post your solution, and ask us to confirm or refute your conclusions. If we see an error in your calculation process, we will point out the error and give you a code reference.

All I will tell you at this point, and I know it will be of little help on its own, is to go to article 220.

traderx · Mar 18, 2005

Re: Wa Admin 01 Test... Help needed

Thanks for the reply charlie b, I started to work the numbers for the first question, but I am stumped on what the demand factor would be for the 13Kva Range for all 4 units... any help would be great.

charlie b · Mar 18, 2005

Re: Wa Admin 01 Test... Help needed

I have to agree that Table 220.19 really is tough to follow, and its notes are even harder to follow. Here?s how I would handle the ranges:

Note 1 tells you to start with the numbers in Column C.

From Column C, for 4 ranges, you get 17 KW of load.

A 13 KW range is larger than a 12 KW range by one KW. Note 1 says to add 5% to the Column C value for every one KW. That means you only add 5% in this case.

5% of the tabulated value of 17 KW is 0.85 KW

17 plus 0.85 = 17.85. That is the number I would use for ranges.

traderx · Mar 18, 2005

Re: Wa Admin 01 Test... Help needed

Yeah... that is what I got after looking in Annex D Example D6

Now... this is what I got for Question 1

1,800 sq ft X 3Va X 4 units = 21,600
Small Applicance 2 X 1500Va X 4 units = 12,000
Laundry (I didn't add to each unit as it states "none of the units contain laundry facilities" so I added it to household at the end)

Table 220.11 Demand Factor
Above total = 33,600

First 3,000 @ 100% = 3,000
Remainer @ 35% (33,600 - 3,000 X 35%) = 10,710

13Kva Range (table 220.19) X 4 units = 17,850
1.2Kva dishwasher X 4 units X 75% = 3,600
.6Kva disposer X 4 units X 75% = 1,800
1,440va compactor X 4 units X 75% = 4320
Omitted A/C
2.5Kva Heater X 4 units = 10,000

Household Laundry = 1,500
equals 52,780 / 240v = 220amps

Now... the closest there is, is 240amps. What did I do wrong

I've started working on Question #2 now

traderx · Mar 18, 2005

Re: Wa Admin 01 Test... Help needed

I got it to work... by adding the total # of laundry in the end... though I can't find in the code book about this, found it in another book, but doesn't state why.... Having a prob with Q #2... comes out lower then the answers given... will post results after I double check

traderx · Mar 18, 2005

Re: Wa Admin 01 Test... Help needed

Ok... I am stumped about Q#2... I doubled checked my work but it still comes out wrong... this is what I did

1,700 sq ft X 3Va X 13 units = 66,300
Small Applicance 2 X 1,500Va X 13 units = 39,000
Didn't add Laundry as it states "not consider house and laundry"
12Kva Range X 13 units = 156,000
1.5Kva dishwasher X 13 units = 19,500
.6Kva disposer X 13 units = 7,800
2,760va A/C X 13 units = 35,880
2.5Kva Heater X 13 units = 32,500 (omitted - smaller)

Total 324,480

Demand Factor from Table 220.32
12-13 units use 41%
41% X 324,480 = 133,036.8 / 240 = 554.32
The Answers are:
1: 610
2: 625
3: 640
4: 655

Not sure where I went wrong.... any help?

==================
I also did Q #4 about the duplex... at first, it came up wrong, but after reading your post at http://www.mikeholt.com/codeforum/ultimatebb.php?ubb=get_topic;f=6;t=000290 I reread the question and did as you suggested and it came out correct, below are my results

1,900 sq ft X 3Va X 2 = 11,400
Small appliance 2 X 1,500 X 2 = 6,000
Laundry 1 X 1,500 X 2 = 3,000
Total = 20,400

Table 220.11 Demand Factor
First 3,000 @ 100% = 3,000
Remaining 17,400 X 35% = 6,090
Total = 9,090

9Kva Range x 2 (table 220-19)= 11Kva
1,320Va dishwasher X 2 X 75% (220-17) = 1,980
600Va disposal X 2 X 75% (220-17) = 900
3,000Va waterheater X 2 X 75% (220-17) = 4,500
5,000w dryer X 2 (220-18 5Kw min) = 10,000
15,120Va A/C X 2 (omitted - smaller then heating)
20,000Va Heater X 2 = 40,000

Total 77,470 / 240 = 322

The closest one to this in Answer #4 @ 321

Will work on the others... hopefully someone will be able to help me out on Questioin #2

snapco · Mar 18, 2005

Re: Wa Admin 01 Test... Help needed

You were right on most of the calc's for question 1 but unless I am wrong it should go like this-

Gen lt load- 13710
Appliance load- 17220 (add all @.75%)
A/C load- 8640 (a/c @ 100%)
Ranges- 18000

Total 57570/240 = 239.8amps or 240 amps

Wa Admin 01 Test... Help needed

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