Wa State 01 General Admin Test Duplex Question

pipeit · Mar 1, 2005

Heres the problem-given optional calc for duplex. 800sq ft ,7kw range ,15kw heat ,3kw water heater ,1320va dw, 600va disposal. 1st i was taught that you assume a dryer unless question makes note of no dryer. If i leave the dryer out of the equation i can actually find one of the 4 available answers. do it for yourself.answer choices for total load amps are 1-190a 2-200a 3-223a or 4-240a.Let me know what you come up with.This is a real test question Wa State General A1 Admin Test.I have more i can post later.
i used sec 220.33 and Table 220.32 to perform calc.

[ March 07, 2005, 06:57 PM: Message edited by: pipeit ]

davenoiz · Mar 7, 2005

Re: Wa State 01 General Admin Test Duplex Question

i did not calc for dryer. my answer was 222 amps.
i don't think the code stipulates that all dwellings get a dryer

snapco · Mar 17, 2005

Re: Wa State 01 General Admin Test Duplex Question

I did not calc a dryer either, I did assume laundry circuit- my answer was 190 amps

33820(each unit)x3 units= 101460 x .45 (220.32)

45,657/240=190.23 amps

Let me know if this is wrong, I have been wrong before-

charlie b · Mar 17, 2005

Re: Wa State 01 General Admin Test Duplex Question

You need to include a small appliance circuit and a laundry circuit (this means the washer, not the dryer). You do not have to include a dryer, if it is not listed.

800 ft2 x 3 = 2,400 VA

Range = 7,000 VA

Water Heater = 3,000 VA

Dishwasher = 1,320 VA

Disposal = 600 VA

Two small appliance circuits = 3,000 VA

Laundry circuit = 1,500 VA

Subtotal VA = 18,820 per unit.

For two units, this is 37,640 VA.

Take 100% of first 10,000 VA and 40% of the rest = 21,056 VA.

Heat = 15,000 VA per unit, times two units

Total VA = 51,056.

Current = 51,056/240 = 212 amps.

Now look at the option provided under 220.33:

Subtotal VA = 18,820 per unit.

Heat = 15,000 VA

Total VA = 33,820 for each unit as a stand-alone.

For three units, this would be 101,460 VA.

Multiply by 45% = 45,657 VA

Current = 45,657/240 = 190 amps.

{EDIT: I have revised the above to make the correction that was pointed out to me by snapco.}

I would go with answer ?A.?

[ March 18, 2005, 11:46 AM: Message edited by: charlie b ]

snapco · Mar 17, 2005

Re: Wa State 01 General Admin Test Duplex Question

I came up with the 33,820 per unit with 2-1500va small appliance circuits instead of 1- I thought that was always the calc to use per 210.11(C)(1)-

I may be wrong but that is how I was taught to calc it-

charlie b · Mar 18, 2005

Re: Wa State 01 General Admin Test Duplex Question

You are right. You need two small appliance circuits plus the laundry circuit. 33,820 is the right number. I will go back and correct my derivation.

That's one "attaboy" to snapco, and one "oops" to me.

Wa State 01 General Admin Test Duplex Question

pipeit

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davenoiz

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snapco

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charlie b

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snapco

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charlie b

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