LED lights glow dimly when switched off

[Greeny]

Hoping I'm not making a mistake here, and that I'm not taking on a safety hazard nightmare.
I'm moving into an older ~40 yr old shop. When buying this property, the shop was not inspected. But, everything looks tidy (wiring is all exposed with unfinished interior walls) and everything seemed to work as it should.
First upgrade is upgrading two 8' fluorescent fixtures to LED shop lights. Basic HD offerings: 4 ft. 64-Watt Equivalent White Integrated LED Shop Light. 4000K Bright White. 3200 Lumens. If it matters. These were the $25 offerings a couple years back and I had them in my basement and garage with no problems.
Installed them in the new/old shop in two strings of 6 each. Loved the lighting! However, when turned off, there was just a tiny bit of glow still visible in each light. Did some googling and one suggestion was that the wrong leg of the circuit could be switched. Neutral vs Hot. My wiring has the power feed, all three wires, coming to the switch, and then going out to the lights. One string had the black wire broken by the switch, the white wire was wire nutted together in the box. I swapped the switch to the white wire and nutted the black wire, and now the lights are totally off when the switch is off. However, on the other string, the white wire was switched through the switch. I swapped those wires around on the switch, and that string now goes completely dark when switched off, so I feel good about that.
BUT... Now I'm worrying that just switching the wires at the switch may simply be masking a larger problem.

Sorry for the rambling background to get to my questions:
Is this something I need to dig deeper into or drag an electrician out to look at? There are other incandescent and fluorescent lights in and around the shop that I haven't looked at.
Was switching the wires at the switch without going back to the breaker a problem? I was ok with swapping wires in a light switch box, not so much with digging around in a breaker box.
I also went around to several outlets with a three light tester for checking polarity and ground, and they all tested good.

 

[rlitman]

I wouldn't worry too much about it. LED lights can glow when off for several reasons.

A barely perceptible glow will always happen in the same way that fluorescent tubes will glow for some minutes, because the fluorescent materials used in both will exhibit some residual luminescence. But this does not sound like your issue.

LED lights, dimmable ones in particular, run on very low amounts of power. Low enough that the pass through current on a neon lighted switch or two-wire timer switch can be enough to get them to glow. If that's the case, it's not actually harmful, but if you need the glow to stop, you might need to replace the switch with one that has a neutral connection.

 

[GRB]

The switch should be breaking the hot connection, not the neutral. Otherwise, when the switch is off, the fixture is hot. Is the black wire hot and the white neutral?

 

[Git]

^^^ This

Ya, you never want to switch the white (neutral)

 

[Greeny]

My glow wasn't a residual luminescence. They were all glowing similarly 24 hours after switching off. And swapping the switched wires immediately eliminated the glow.

I don't know which wire is actually hot and which is neutral, but the two circuits are wired oppositely, so one of them is wrong. I just don't know if it is necessary to tear into it to fix it, just to get the wire colors right.

And how can I tell if the black is hot?

 

[Innovate1]

LED lights can glow if there is some leakage at the switch - if it is a lighted switch or is electronic. I had the issue on one circuit and put one regular incandescent bulb in to fix it. But you may have other issues given your description of your wiring.

 

[scooterbum46]

And how can I tell if the black is hot?

Not trying to hurt your feelings, but maybe you should call an electrician - you've already created one potential dangerous issue in apparently switching the neutral on one circuit. Telling which wire is hot is very basic - it sounds like you are already in over your head..

 

[Greeny]

Not trying to hurt your feelings, but maybe you should call an electrician - you've already created one potential dangerous issue in apparently switching the neutral on one circuit. Telling which wire is hot is very basic - it sounds like you are already in over your head..

Yeah, I'm over my head, but I don't think I've switched neutral on any circuits. Simply swapped which wire runs through the switch. That doesn't change any configuration on an outlet, socket or breaker.
It seems to me that some of the circuits may be run without regard to proper wire color, I'm partly asking if I should worry about calling in an expert just to correct this.

 

[Greeny]

LED lights can glow if there is some leakage at the switch - if it is a lighted switch or is electronic. I had the issue on one circuit and put one regular incandescent bulb in to fix it. But you may have other issues given your description of your wiring.

Not lighted or electronic switches. Old school flip switch.

 

[GRB]

Any decent tester will tell you about polarity. Plug in the outlet or test leads if the unit is open.

 

[Innovate1]

Yeah, I'm over my head, but I don't think I've switched neutral on any circuits. Simply swapped which wire runs through the switch.

You just described switching the neutral whether you realize it or not... That means using the switch in the neutral wire rather than the hot wire.

 

[Greeny]

You just described switching the neutral whether you realize it or not... That means using the switch in the neutral wire rather than the hot wire.

I moved the switch from the neutral to the hot side. No change to the polarity at the light, only a change to the wire switched open or closed.
My outlets polarity test correct with a plug-in tester.

These lights are switched differently than what I think is standard or normal. The power goes down to the switch box, where one of the wires is run through the switch, then then up to the lights.
So, instead of one run of wire from the switch to the light switching the hot side, there is two runs of wire, from the breaker in and a switched one out.

This is tough to explain clearly, and I'm probably butchering proper terminology.

 

[b-boy]

You need some pictures to make it clearer.

 

[Greeny]

Should I be worried if my wiring doesn't follow standard color coding?

Polarity is ok everywhere tested. Grounds are ok everywhere tested. I found two light switches on the neutral leg. I switched them over to the hot leg. All is well now.
But one of the circuits has the hot on the white wire.

 

[b-boy]

If it's really a hot wire, put some black tape around it so it doesn't cause confusion in the future. I've seen that done many times with a light switch, especially when the power goes to the fixture instead of to the switch box.

 

[CJ7VFR]

If it's really a hot wire, put some black tape around it so it doesn't cause confusion in the future. I've seen that done many times with a light switch, especially when the power goes to the fixture instead of to the switch box.

That's called a switch loop. The ends of the white wire are colored black using some electrical tape, or a Sharpie, in order to identify the wire as now being a switched hot and not a neutral.

This was done a lot in the past when the power was coming into the light fixture first, versus having the power come from the switch first.

Since the newer versions of the NEC have mandated that all switch boxes must have a neutral wire in them, the practice of installing a switch loop is not used unless there is a way to easily run a neutral to the switch box in the future.

Jim

 

[sparky 1971]

I haven't read every post so forgive me if this has been mentioned. Do you have a locator light on a switch? This would be the switch with an "orange glow" that can only be seen in the dark. I have had two service calls for this same problem. Without going into details, putting a plain old switch in solved the problem

 

[dogdog]

This problem have been a topic for youtubers for a while Not something new... basically it's just cheap bulb drivers .... and or you have an inductive load or wiring issues... such as I have installed the switch on the neutral or used the ground as neutral or similar (screw up the grounding) that some how retain a charge....

as for the bulb issue...these 4 videos explains it well...these 3 guys are my fav

 

[zeke67]

When the posters are saying "switched neutral" or some variation of that phase, they mean the electric switch is on the neutral wire. They don't mean you swapped neutrals.

 

[PassnThru]

LED lights can glow if there is some leakage at the switch - if it is a lighted switch or is electronic. I had the issue on one circuit and put one regular incandescent bulb in to fix it. But you may have other issues given your description of your wiring.

Not lighted or electronic switches. Old school flip switch.

I haven't read every post so forgive me if this has been mentioned. Do you have a locator light on a switch? This would be the switch with an "orange glow" that can only be seen in the dark. I have had two service calls for this same problem. Without going into details, putting a plain old switch in solved the problem

I put a LED bulb in a fixture in my bathroom one day. That night, I went to bed (with a clear view into the bathroom) and noticed that the new LED I had installed was glowing very slightly. It was faint, but noticeable. I finally determined that the lighted switch it was attached to was letting through just enough current for it to glow where a regular incandescent bulb would just shrug it off.
I know you said you didn't have a lighted switch but I would swap it with a new one or another one in the house just to see. You are getting a little leakage into the light.

 

[dogdog]

When the posters are saying "switched neutral" or some variation of that phase, they mean the electric switch is on the neutral wire. They don't mean you swapped neutrals.

just view those 4 links... it'll explain why, worth the time... I don't have this problem with any of the bulbs I have, cause they have switch mode drivers inside ( I actually opened few that went bad)... but cheaper bulbs that is mentioned that uses capacitor droppers will have this issue... all those youtuber explained this... reasonably well.

 

[TractorJeff]

I moved the switch from the neutral to the hot side. No change to the polarity at the light, only a change to the wire switched open or closed.
My outlets polarity test correct with a plug-in tester.

These lights are switched differently than what I think is standard or normal. The power goes down to the switch box, where one of the wires is run through the switch, then then up to the lights.
So, instead of one run of wire from the switch to the light switching the hot side, there is two runs of wire, from the breaker in and a switched one out.

This is tough to explain clearly, and I'm probably butchering proper terminology.

I think this is a switch loop as described by several other posters?
I'm thinking, did you check the polarity of the outlets that your LEDs are plugged into?

 

[Greeny]

I think this is a switch loop as described by several other posters?
I'm thinking, did you check the polarity of the outlets that your LEDs are plugged into?

Yes, the polarity checks good, according to the basic 3 light tester I'm using. The wire colors are just backwards on some circuits.

 

[cderalow]

Yes, the polarity checks good, according to the basic 3 light tester I'm using. The wire colors are just backwards on some circuits.

IF it were me, and all else being equal (meaning you've solved the issue with the light bleed through/glowing when switched off)

on the outlets/switch everything that has wires backwards (white = hot, black = neutral) I would indicate on the back of the corresponding cover plate that it is the case.

last thing you want is some professional coming in and finding a hot 'neutral' the hard way

 

[nsula_country]

I have some LED motion lights that glow faintly at night.

Current Leakage, cheap drivers.

CT