This weeks 2014 Code change comes from section 200.4(B) which deals with neutrals grouped in panelboards or enclosures. Then identifying them so that you don’t mistakenly disconnect the wrong one and send an over or under voltage to a piece of equipment and possibly burn it up. This section requires us to identify the neutral conductor for each circuit or circuits it serves. This is for single circuit or multi-wire circuit.
Over the years I have seen electricians working on circuits only to disconnect the neutral to move it around to make room for another neutral conductor, only to disconnect it while the circuit it serves was still energized. This resulted in a burnt out refrigerator or computer that was on a multi-wire circuit.
I have seen a few good ways to ID the neutrals by either numbering them with the corresponding circuit number(s) on each neutral or grouping them with a piece of the sheath from NM cable marked with the circuit ID.
There are a couple of Exceptions where you can tell which neutral goes with a particular circuit of a cable or conduit installation, or when there just isn’t room to mark the wire in an existing installation where the conductors are pulled through a box or enclosure without splices.
Till next time work safe be safe and keep an eye on your helper.