1/30 Recessed LED Lamps Glows in Dark

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MikeAqua

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#270316 4-May-2020 09:43

We have 30 recessed mains powered LED lamps in our house. All the same model and installed at the same time.

One of these glows for several hours after being switched off. None of the other lamps in the house including those on the same circuit do this. If you hold something up to the lamp, no light visibly shines onto anything. It just glows very softly in the dark (looks like phosphorescence) and the glow is distributed evenly across the lens.

I have two questions: -

1) Is this indicative of some sort of wiring issue (I don't think it is).

2) Mainly I'm just curious ... what causes this and why only that lamp?

Mike

mdf

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#2476150 4-May-2020 10:01

House wiring acting as a capacitor?

chevrolux

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#2476151 4-May-2020 10:01

I'm purely guessing... but maybe there is something wrong with the driver? LED's don't need much to light up, so perhaps its a capacitor in the driver just slowly discharging?

Edit: mdf beat me to it. but seems plausible?

frankv

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#2476152 4-May-2020 10:02

Is the glowing one on a 2-way circuit? I.e. 2 switches at either end of a hallway or similar?

We have that, and the LED glows slightly too. I'm assuming it's some kind of induced current due to the way the circuit is laid out.

richms

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#2476160 4-May-2020 10:07

Quite common with LEDs with buck converters in them, few microamps from capacitive coupling across switch wires and they will do that. Longer switch wires means more coupling. It will usually be only one of them that does it because it will go to the one with the lowest foward voltage.

Often there will be a resistor inside to shunt the current but guess the ones you have lack that.

Richard rich.ms

mrdrifter

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#2476170 4-May-2020 10:35

I have the same thing occurring with one single LED, just a gentle glow that is only really visible at night. The LED in question is on a 2 gang switch which also controls the outside spots and I'm thinking it is either induction from supply wires and others running up the wall together or there is some strange loop behind the switch, I haven't opened it up to have a look as yet.

MikeAqua

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#2476196 4-May-2020 11:17

It's on a one way switch. The only light on this switch. Located in a walk through wardrobe.

Mike

richms

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#2476197 4-May-2020 11:19

It may still be wired with a switch wire looped down from the fitting which is when its most going to happen. If it doesnt bother you then ignore it. Free lighting that is using power that would otherwise just be wasted ;)

Richard rich.ms

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Rickles

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#2476210 4-May-2020 11:32

>Located in a walk through wardrobe.<

Leakage from Narnia?

MikeAqua

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#2476373 4-May-2020 15:12

Rickles:

>Located in a walk through wardrobe.<

Leakage from Narnia?

Nah, no electricity there.

Mike

gregmcc

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#2476490 4-May-2020 16:34

MikeAqua:

We have 30 recessed mains powered LED lamps in our house. All the same model and installed at the same time.

One of these glows for several hours after being switched off. None of the other lamps in the house including those on the same circuit do this. If you hold something up to the lamp, no light visibly shines onto anything. It just glows very softly in the dark (looks like phosphorescence) and the glow is distributed evenly across the lens.

I have two questions: -

1) Is this indicative of some sort of wiring issue (I don't think it is).

2) Mainly I'm just curious ... what causes this and why only that lamp?

This indicated that there is a small induced voltage in the wiring or a light switch that is 100% working (allowing a small voltage thru). There are an accessory that can be wired in at the light switch that rectifies this (the exact name escapes me at this time).

I guess the design of the power supply in these lights allowing the slight glow, some of them when this issue is present cause the light to flash instead.

Talk to your electrician they should be able to sort something out for you

richms

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#2476493 4-May-2020 16:37

mdf:

House wiring acting as a capacitor?

That guys videos are hillerious. Watch all of them.

Richard rich.ms

mdf

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#2476500 4-May-2020 16:48

richms:

mdf:

House wiring acting as a capacitor?

That guys videos are hillerious. Watch all of them.

Waaaay ahead of you! Patreon is a wonderful thing. Not sure what it is about Canadian youtubers, but they seem statistically over-represented in my subscriptions (Electroboom, AvE, Matthias Wandel and John Heisz). In AvE's words, I guess the frozen hell hole of Hoth prompts you to go inside and film something?

snnet

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#2477163 5-May-2020 16:48

A simple load correction device will fix this. You're lucky it's only 1 because they're around the $50-$80 mark +GST