At my request a few years ago an electrician pulled a 30amp 2 pole breaker out of the panel and replaced it with two single pole 15 amp breakers and connected them to the existing 10/3 cable.
10/3 runs from the two 15amp breakers to a jbox. Is it still code (NEC) to construct two separate 15 amp circuits from the jbox in this scenario? if so any suggestions for labeling the jbox?
Thanks.
Under current (and quite a few years back, now) code, the handles of the two 15A breakers should be tied together, so when you shut off one half of the MultiWire Branch Circuit you shut off both halves of it.
Otherwise, yes, you can split that out into two separate 15's from a junction box.
Labeling? The numbers of the slots for the breakers that feed it, and MWBC, I suppose. No label is required by code there. But I'm quite fond of disambiguating what breaker(s) feeds what box.
