LSStream
Member
- Location
- Bucks County, PA
- Occupation
- Engineer
I was replacing a single pole rocker switch fed by 14/2 NM-B in a single gang box (herein "switch box") with a Lutron RadioRA3 SP switch (for a dining room ceiling fixture) and I discovered current on the grounded conductors ("neutral" or "white" wires). I initially suspected an open upstream neutral, but some basic troubleshooting revealed that there was polarity reversal of the line grounded/neutral/white and the ungrounded/hot/black conductors. I located the next upstream device (living room duplex receptacle in single gang box, herein "duplex box"), which had correct polarity (confirmed after separating all conductors in this box from the device). I then confirmed that there was continuity between the white conductor in the duplex box and the black conductor in the switch box and vice versa. BTW, the switch box is the last device on the run.
There is no intervening device or junction box that I am aware of (and I have all circuits well mapped out from original construction), but I do recall that during a major kitchen renovation about 6 months ago, the electrical contractor for the job told me he was going to use a UL listed inline NM-B splice (not sure if Tyco/TE or NSI), since a couple devices on that circuit were being eliminated and this would simplify wiring (presumably splicing the load NM-B cable from the duplex box to the line NM-B cable of the switch box. I never personally used these devices, but was aware of them, and didn't see an issue, so I said ok. I discussed by findings with him and asked if polarity reversal was possible with this device (i.e., if wired incorrectly), and he said it's impossible to wire these wrong. Of course, I see no other potential culprit and I maintain that this device is the source of the reversal. Not having direct experience with these inline NM-B splicers, can anyone weigh in on the possibility of mis-wiring them, perhaps if done by one of the less experienced crew members?
Normally, I would just run a new NM-B from the duplex box to the switch box and bypass the spliced cables. However, wall access is not feasible (expensive custom painted artistic walls in the dining and living rooms, brand new kitchen, etc.) and basement access might not be great because the switch box is in an HVAC return stud bay, which precludes vertical runs of NM-B from the basement and box is also walled off with Thermopan.
So... is it acceptable to merely tape the switch box white conductor with black tape (to indicate an ungrounded conductor) AND the switch box black conductor with white tape (to indicate a grounded conductor)? If not, what else might I consider? Thanks.
There is no intervening device or junction box that I am aware of (and I have all circuits well mapped out from original construction), but I do recall that during a major kitchen renovation about 6 months ago, the electrical contractor for the job told me he was going to use a UL listed inline NM-B splice (not sure if Tyco/TE or NSI), since a couple devices on that circuit were being eliminated and this would simplify wiring (presumably splicing the load NM-B cable from the duplex box to the line NM-B cable of the switch box. I never personally used these devices, but was aware of them, and didn't see an issue, so I said ok. I discussed by findings with him and asked if polarity reversal was possible with this device (i.e., if wired incorrectly), and he said it's impossible to wire these wrong. Of course, I see no other potential culprit and I maintain that this device is the source of the reversal. Not having direct experience with these inline NM-B splicers, can anyone weigh in on the possibility of mis-wiring them, perhaps if done by one of the less experienced crew members?
Normally, I would just run a new NM-B from the duplex box to the switch box and bypass the spliced cables. However, wall access is not feasible (expensive custom painted artistic walls in the dining and living rooms, brand new kitchen, etc.) and basement access might not be great because the switch box is in an HVAC return stud bay, which precludes vertical runs of NM-B from the basement and box is also walled off with Thermopan.
So... is it acceptable to merely tape the switch box white conductor with black tape (to indicate an ungrounded conductor) AND the switch box black conductor with white tape (to indicate a grounded conductor)? If not, what else might I consider? Thanks.
