Inverter replacement compatibility

[jaggedben]

You're probably not dealing with an AHJ when you're just replacing an inverter anyway.

The code did allow a single functionally grounded conductor in pv circuits to be identified only at terminations. (200.6(A)(5) in 2014 NEC.) But just about every system I saw transitioned to white THWN-2 in EMT so that's the one I'd be concerned about. And no, like I said above I'm not repulling that if there's no inspection, I'll leave notes and put different labels on the inverter instead, as discussed above. In my humble opinion anyone who can't deal with that doesn't meet the requirements of 690.4(C).

 

[pv_n00b]

Which white wire is that? Even in the days of grounded inverters I never had white wires out in the array.

I've seen many white wires used and white was an available color for a long time. But also black wires with white tape on the ends were often used. Those are easy enough to change, remove the tape. Of course, if someone used red wire then all the wire is white after a few years in the sun. As JaggedBen wrote, once transitioned off the roof and into THWN-2 white conductor was used for the grounded conductor.
While the code allows other colors to be marked on the ends as white there is no allowance for changing white to another color using a similar end marking.
AHJ review or not, you do not want to set up someone to get hurt in the future by leaving an unmarked white conductor in the system if it is ungrounded. Some people are remarkably blase about any conductor they see that is white and assume they can't get shocked touching it.

 

[jaggedben]

...Some people are remarkably blase about any conductor they see that is white and assume they can't get shocked touching it.

And that is stupid whether the system still has the old ground-fault-fuse inverter or has been updated. In retrospect, white should never have been used in these systems. But also, I'll refer again to 690.4(C). Be careful out there and never make assumptions.