Downstairs light go...
 

  You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more

Downstairs light gone rogue

22 Posts
18 Users
14 Reactions
97 Views
Posts: 8771
Full Member
Topic starter
 

The downstairs LED light, after a couple of years, has suddenly decided it's going to completely ignore the state of the two light switches and glow at a low level, enough to dimly light the bottom of the stairs.

This goes against everything I know. There is no dimmer switch. The light state should be binary on or off. NOT A LITTLE BIT ON NOT 0.25 ON JUST ON OR OFF 1 OR 0.

What is this voodoo?


 
Posted : 03/12/2023 10:24 am
Posts: 5807
Free Member
 

Sounds odd. I've only seen it when I replaced an incandescent with an led in a circuit with a combined dimmer/timer switch. But you say it's a simple on/off, so sorry, not a clue!


 
Posted : 03/12/2023 10:40 am
Posts: 1130
Free Member
 

It’s what some LEDs do when they fail. Something to do with small amounts of residual energy in the drivers. Time to replace it.


 
Posted : 03/12/2023 10:44 am
Posts: 44146
Full Member
 

I have seen this as well with a failed LED lamp in a two way switching setup like you mention.  I can only think the failed lamp led to a short circuit that allowed some current thru.  Going the "wrong way" around the two way switching circuit?

replace the lamp and I bet its all OK - mine was


 
Posted : 03/12/2023 10:45 am
Posts: 645
Full Member
 

It’s likely a ghost voltage (induced by an adjacent cable) but I’m not sure about the correct way to solve it.

If changing the light doesn’t fix it I’d call an electrician.

Edit: I think the issue is probably the light, ie it’s failed in such a way that the low ghost voltage is causing a small current to flow through the LED.


 
Posted : 03/12/2023 10:55 am
Posts: 8771
Full Member
Topic starter
 

Okay replacing sounds like a sensible first step. Cheers


 
Posted : 03/12/2023 10:59 am
Posts: 5686
Full Member
 

This happens with my outdoor lights at times, they are led lamps, and despite being switched off will sometimes glow dimly. I just figured it was malignant spirits!

Also, read the title as rouge (red), thought Roxanne was posting 🥁


 
Posted : 03/12/2023 11:05 am
Posts: 22922
Full Member
 

It’s likely a ghost voltage (induced by an adjacent cable) but I’m not sure about the correct way to solve it.

If changing the light doesn’t fix it I’d call a priest


 
Posted : 03/12/2023 12:03 pm
 zomg
Posts: 850
Free Member
 

You’ll need a young priest though: the old ones only trained with haunted incandescent bulbs.


 
Posted : 03/12/2023 12:19 pm
Posts: 9069
Free Member
 

 
Posted : 03/12/2023 1:10 pm
oldnpastit, fasthaggis, oldnpastit and 1 people reacted
Posts: 2616
Full Member
 

Sounds remarkably similar to my issue a few weeks back. https://singletrackmag.com/forum/topic/house-electric-light-problem/

My problem was that one of the two 2-way switches had failed.

Changed that and all is good 


 
Posted : 03/12/2023 1:20 pm
Posts: 775
Free Member
 

This does indeed sound like the driver in the light is on the way out.  <br /><br />

ref comments above regarding perfectly functioning leds also staying dimly lit, leds are capacitive loads (vs resistive on incandescent lamps), effect being if you only have a low load on a circuit you’ll get this happening. Way to solve it is to fit a suitable capacitor across the line and neutral (FYI I’m a spark, so probably best not do this unless you really know what you’re doing!)


 
Posted : 03/12/2023 1:35 pm
Posts: 8771
Full Member
Topic starter
 

Both upstairs and downstairs switches literally have no effect whatsoever. Thankfully no shocks...

Just looked and the light turns off now! It still has only partial brightness when on. When i turn it off, it fades off over a second.

Wondered if with all the rain dampness had got in and was affecting the wiring perhaps?

Swapped with a working bulb - it is just the bulb on the way out. Last time had a bulb die it just stopped working altogether none of this weirdness!


 
Posted : 03/12/2023 1:40 pm
Posts: 22922
Full Member
 

it is just the bulb on the way out. Last time had a bulb die it just stopped working altogether none of this weirdness!

You need to encourage it to go towards the light


 
Posted : 03/12/2023 2:00 pm
Posts: 8771
Full Member
Topic starter
 

You need to encourage it to go towards the light

I'm interested in the inferred lights! How do they work then? Deduction rather than conduction?


 
Posted : 03/12/2023 3:27 pm
tjagain and tjagain reacted
Posts: 0
Free Member
 

 
Posted : 03/12/2023 5:38 pm
Posts: 13240
Free Member
 

It’s likely a ghost voltage (induced by an adjacent cable) but I’m not sure about the correct way to solve it.

If changing the light doesn’t fix it I’d call a priest

👍😊


 
Posted : 03/12/2023 5:42 pm
Posts: 7076
Full Member
 

Could be someone is trapped in the upside down trying to communicate with you.


 
Posted : 03/12/2023 7:25 pm
Posts: 4643
Full Member
 

I have this exact issue. The cause and resolution is remarkable. I thought it was hall effect with current being invoked in a wire based on alternating current being present in a cable lying parallel with it.  Nope that’s  not the root cause. <br /><br />Instead, as switches fail the contacts often become closer to each other.  Eventually they become so close that the air between them acts as a dielectric (as in a capacitor) and current spuriously flows.  LEDs are so frugal in their use of electricity that even a teeny tiny current will make them light up.

change your light switch.

some LEDs have shunts which suppress this issue.


 
Posted : 03/12/2023 8:00 pm
Posts: 5153
Free Member
 

New house and new bicycle needed I’m afraid.


 
Posted : 03/12/2023 8:18 pm
Posts: 8771
Full Member
Topic starter
 

change your light switch.

I did, I swapped the upstairs and downstairs bulbs with each other and the issue followed the bulb not the switch. It's the bulb that needs changing in this case 🙂 Shame I didn't think to try that this morning lol.


 
Posted : 03/12/2023 9:22 pm
hot_fiat and hot_fiat reacted
Posts: 10761
Full Member
 

How many STWers does it take to change a light bulb?

At least 16 so far and we haven't even had a big hitter along to blame the tories yet.


 
Posted : 04/12/2023 9:14 am
tjagain, avdave2, tjagain and 1 people reacted
Posts: 10315
Full Member
 

Was the light fitting eathed?  I've seen this before with some but not all bulbs and I wondered if it was capacitive coupling from the unswitched wire through to earth.  It could slowly charge the circuits internally sufficiently to glow occasionally


 
Posted : 04/12/2023 9:18 am

6 DAYS LEFT
We are currently at 95% of our target!