max overcurrent protection size?

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J-R

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What would be max size overcurrent protection for this situation?

24 #10 thhn in 1 1/2 emt (ambient temp 100f) branch circuits serving continuous lighting load and multi outlet recepticles?

#10 thhn 40a
ambient temp adj .91
310 15 b2a correction 45%

40x.91x.45=16.38

240.4 b1 is not met because of mulit outlet recepticles branch circuit

does 1.25% for continuous load apply in this situation?

I would think 15a would be max

Thanks for any help
 
So we have no idea what the load is. If the load is 10 amps then a 20 amp breaker could work. This is a bad question. The 125% does not enter into the equation, IMO.
 
IMHO, 15 amp would be the max OCP for the conductors feeding any multi-outlet branch circuits feeding cord and plug connected portable laods.
Your continuous lighting would have to be calculated at 125% so with a conductor ampacity of 16.38, the lighting load would be limited to 13.1 amps but could be on a 20 amp OCP device.
 
What im trying to understand is as long as your calculated load is under 16.3a
it would still be ok to use a 20A breaker in this situation?
 
Add these...

The distance (might be required to be considered) and including a deduction count of the sum of the fill of the conduit itself!

Your item circuit load is individual and a sum of individual loads to the circuits served needs to be determined and established!





Hope that helps...
 
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