correct amount of circuits

[Dennis Alwon]

There are two different subjects here. You can round down for amperage 220.5 (B) but not for the number of circuits.

If you can round down for amperage then the number of circuits can possibly be reduced. What good is rounded down for amperage if you can't use it. Where does the code support your statement?

 

[yired29]

If you can round down for amperage then the number of circuits can possibly be reduced. What good is rounded down for amperage if you can't use it. Where does the code support your statement?

I am not saying you can't round down for amperage and yes it can result in needing one less circuit.

That is why my second post I believe post #5 said 3 - 30 amp circuits would work. Treat the load a three separate loads instead of treating it like a feeder.

For example when sizing a one family dwelling service and the question asks what is the minimum number of 15 amp branch circuits required for the general lighting load of a 6150 VA calculated load?

6150 / 120 = 51.25

51.25 / 15 = 3.42 circuits

This would require 4 - 15 amp circuits.

 

[peter]

For .03 over the limit, I would forget about it and permit 3 circuits. But how expensive is another 30 amp breaker?
~Peter

 

[normbac]

For .03 over the limit, I would forget about it and permit 3 circuits. But how expensive is another 30 amp breaker?
~Peter

not just a breaker long distance to 3 way switching

 

[LarryFine]

Each fixture is 280 watts at 277 volts is virtually 1 amp apiece. On a 30 amp circuit you can have 24 amps for continuous load.

The 280w/277v x 24 = 24.26a, so the question is whether a 30a circuit is adequate.

With other than a 60-deg wiring method, I would not hesitate to use only 3 circuits.

 

[satcom]

Fluorescent Electronic Ballasts are great, no worries about overloaded raceways, that with poor design, can get hot eniough to make an egg sandwich.