kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
I agree, delete 310.15(B)(7) and modify the rules in 220 so that we have a real world load. Then size the residential feeders and service entrance conductors like any other conductors.
See, I should be writing the code.
Chris
Still not all that simple IMO. So you calculate a dwelling load to be 140 amps with a modified art 220. All this means is the minimum size service or feeder for that dwelling is 140 amps. In reality most people are still going to supply this with a 200 amp service or feeder. If you put in a panel with a 200 amp main breaker you still need a 200 amp conductor even though the calculated load was 140. The rule we have now simply recognizes there is typically enough diversity to the load, that a 4/0 aluminum or 2/0 copper is sufficient even though they have an ampacity of less than 200. Changing art 220 will not change overcurrent protection rules or conductor ampacity rules, it only changes the calculated load.