Size of Feeders

[osaengineers]

I was told be someone that the code says that you can only load up panels and services up to 80%. I said that I dont know where that is stated but I do now that the feeders are sized based on 100% of non-continous load and 125% of continous load (not using 100% devices). Am I correct or is he?

Thanks

 

[suemarkp]

The 80% and 125% are kind of saying the same thing. If you have an 80 amp load that is not continuous, then you can put that on an 80A feeder or service. If that load is continuous, then you need 80*1.25 = 100A feeder or service.

So a 100A feeder or service can serve an 80A continuous load or 100A non-continuous load or a sum of mixed loads where the continuous ones are multiplied by 1.25 and the total sum is 100A or less.