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I was installing new LED lamps on my kitchen, which seemed to be functioning well. After turning off the lights, the newly installed lamps still had a dim light, that kept itself for quite long.

I've measured around 60VAC on the OFF switch for these lamps and 110VAC for the OFF switch attached to another lamp.

After lots of head scratching, I've tried to plug just one leg of the LED lamp into a plug hole, result on the picture below.

One leg connected, but partially ON

Why does this happen? How can I prevent it? Does it take a toll on my electrical bill?


marked as duplicate by Eugene Sh., Edgar Brown, Finbarr, Bimpelrekkie, RoyC Mar 25 at 17:25

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The bulb that you are holding in the picture that you posted very possibly has live mains on it. If so, the photo subject is at grave risk of electrocution.

Being in contact with a grounded or "somewhat grounded" object or surface at the same time could result in a possibly fatal electric shock.


Lightly edited exerpt from my other answer (posted just now).


If reversing the polarity of the circuit or using the other "leg" fixes the problem then you probably have Phase / Live connected to the circuit at all times and it is improperly wired and a "death trap".

If only lighting equipment without grounded metal accessible to users is used then you may not have anyone killed.

But if you use equipment on the circuit where neutral and ground are connected (as happens even though it shouldn't) then such equipment will be "safe enough" on a properly connected circuit BUT lethally dangerous on this one.

Getting it fixed while everyone is still alive is liable to be "a good idea".

  • \$\begingroup\$ For info, nobody was killed or injured in the making of the above picture. Also, I'm not sure about the place you live, but I took some electric shocks when I was a kid due to unprotected wires or poorly connected plugs. Hurt a bit, but I've never heard of anyone actually getting killed. I do understand the issue gets worse if the current path passes through the victim's heart. \$\endgroup\$ – Mefitico Mar 20 at 11:29
  • \$\begingroup\$ Nonetheless, your concern is appreciated. \$\endgroup\$ – Mefitico Mar 20 at 12:31
  • \$\begingroup\$ @Mefitico I'm somewhat gobsmacked by your response. I didn't think anyone had been killed as if you had been you probably wouldn't have posted the picture. The terms 'hazard', 'death trap' and 'lethally dangerous' simply indicate that you COULD have easily died and "next time you or someone else might. | About 300 people die from electrocution in the USA - where mains is 110VAC. In many countries the rate is probably higher. If the US rate applies worldwide that's 5000 per year. People who die of electrocution tend not to tell you about it. | Try not to die - fix the circuit. \$\endgroup\$ – Russell McMahon Mar 21 at 8:01
  • \$\begingroup\$ You make feel like I should keep answering or you'll assume I'm dead... Where did this statistics for electrocution deaths came from? Are they accounting only for domestic accidents? I know in Brazil around 90 people die per year due to lightning strikes, I've seen a power station exploding (in video), and I know electric current is really dangerous to the heart, but I've always thought electric shocks from unprotected wires or so could be hurtful but not deadly (specially for people wearing shoes) . \$\endgroup\$ – Mefitico Mar 21 at 12:00
  • \$\begingroup\$ @Mefitico Stats were from 'official' US figures - similar results on a umber of sites. || You said "but I've always thought electric shocks from unprotected wires or so could be hurtful but not deadly (specially for people wearing shoes) ." PLEASE now reconsider your beliefs. MANY domestic electrocutions occur due to contact with live wires. I have been involved with electricity for 55+ years. I'm a professional engineer (ME (elec fwiw)). I too have had numerous shocks - and was 'lucky' to survive some. ... \$\endgroup\$ – Russell McMahon Mar 21 at 23:39

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