jaggedben
Senior Member
- Location
- Northern California
- Occupation
- Solar and Energy Storage Installer
It might also be worth noting that the NEC has the general provision for sizing feeder neutrals to the calculated load, but AFAIK had no such provision for branch circuit neutrals. So there's a bit of a catch-22 here. Unless the manufacturer gives you a 705.95(B) letter, you need a full size neutral (i.e. same as ungrounded conductors) for the branch circuit. But if the manufacturer can't tell you that because there's a teeny weeny bit of non-sensing current on the neutral, then you need a full size neutral for the branch circuit even if it's a ridiculously teeny-weeny bit. So why should they tell you how much if it makes no difference? (Answer: for feeders, but you get my drift.) I'd note that electric dryers and ranges have the same problem. There's an incredible amount of wasted metal in neutrals out there in the world. Maybe that's the point.