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Number of circuits required for the lighting load of an 8000 sq.ft. residence?
Any guesses? :thumbsup:
 

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ONE! They're all 9W LEDs. What do I win?
P&L
 

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Homework question Tangent?
 

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Well this is my guess? 17
(14) 15A + (2) 20A small appliance loads + (1) 20A laundry
Are required small appliance, and laundry branch ckts. part of the lighting and general use branch ckts calc.?
What about range and dryer loads?
A/C, water heater?
 

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Number of circuits required for the lighting load of an 8000 sq.ft. residence?
Any guesses? :thumbsup:
3 20 amp circuits-- laundry and small appliance branch circuit.

8000 x 3 = 24000

first 3000 @ 100% 3000
[email protected] 35% = 21000 x .35 = 7350

15 amp x 120 v = 1800
20 amps x 120 = 2400

7350/ 1800 = 4.08 Technically 4 circuits should work however I am not certain 220.5 would apply here so I would say 5 circuits @ 15 amps

7350/2400 = 3.06 therefore 4 - 20 amp circuits Plus the 3 for the small app
means

7- 20 amp circuits

or

3 - 20 amp circuits and 5 - 15 amp circuits
 

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3 20 amp circuits-- laundry and small appliance branch circuit.

8000 x 3 = 24000

first 3000 @ 100% 3000
[email protected] 35% = 21000 x .35 = 7350

15 amp x 120 v = 1800
20 amps x 120 = 2400

7350/ 1800 = 4.08 Technically 4 circuits should work however I am not certain 220.5 would apply here so I would say 5 circuits @ 15 amps

7350/2400 = 3.06 therefore 4 - 20 amp circuits Plus the 3 for the small app
means

7- 20 amp circuits

or

3 - 20 amp circuits and 5 - 15 amp circuits
Dennis, shouldn't you add the first 3,000 VA to whatever gets multiplied by 35%?

3,000+(21,000 x 0.35) = 10,350
 

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I forgot about this:

220.42 General Lighting. The demand factors specified in
Table 220.42 shall apply to that portion of the total branch circuit
load calculated for general illumination. They shall
not be applied in determining the number of branch circuits
for general illumination.
I wish to amend my previous post.

Technically, only one should be required.
 

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Dennis, shouldn't you add the first 3,000 VA to whatever gets multiplied by 35%?

3,000+(21,000 x 0.35) = 10,350
Yes-- did this at 4 am or so Lying in bed just like Brian Wilson did... thanks

10350/1800=6 15 amp and 3 - 20 amp circuits
 

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I forgot about this:



I wish to amend my previous post.

Technically, only one should be required.
I bet the test will not come up with that as an answer....LOL
 
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