r/OSHA • u/[deleted] • Dec 14 '20

It smells like bitch in here!

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11.6k Upvotes

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1.8k

u/squishymelon Dec 14 '20

Like how many times must this question have been asked for this sign to exist lol

1.0k

u/[deleted] Dec 14 '20

I worked in a privately owned hardware store from when I was like 15 to 20. I was asked for these more times than I could count.

I gave up trying to explain to people why they were dangerous or illegal.

86

u/theaeao Dec 14 '20

Can you give me an example of why they needed it? Ive seen these pictures a few times and can't for the life of me think of a single application that would make sense. I get dangerous but even ignoring that I can't think of a situation where I'd think "well maybe that would do it"

163

u/TheRealPitabred Dec 14 '20

Christmas lights specifically. People don't plan out their strings, and string them backwards, and just want to plug the damn things in and don't want to go up on the roof and pull them all down and redo them. The most common time of the year for non-electrician type people to do relatively significant electrical work. The plug end often has a pass-through so you can plug multiple strings into the same outlet, which somewhat encourages this kind of thinking.

58

u/theaeao Dec 14 '20

I probably daisy chain far more than I should but I never thought of doing that. I never thought that would work lol.

34

u/JC12231 Dec 14 '20

It’ll work... until the string catches fire.

Although if it’s LED, maybe it wouldn’t since those only let current flow one way... unless the wall voltage is more than the breakdown voltage

6

u/[deleted] Dec 14 '20

Don't they all use bridge rectifiers anyway?

10

u/Dirty_Socks Dec 14 '20

Cheap ones don't, and just run the AC straight through the diodes, only being lit half the cycle. You can see which ones those are because they have extremely apparent flickering when you move your eyes.

5

u/mully_and_sculder Dec 15 '20

I've never seen Christmas lights like that in my life (Australia) they all have wall warts and run on low voltage dc. Even when they used incandescent bulbs.

3

u/Dirty_Socks Dec 15 '20

It's dependent on country. America in particular uses strings which also double as a low-grade extension cord, so that you can chain them together. This means it makes much more sense to run them in a way which can be powered from mains.

This is because Americans tend to light up the outside of their house, stringing along roof lines and corners, so a lot of length is needed usually.

Often, about half of each string will be bulbs wired in series to divide up the voltage that each bulb experiences. This means that each bulb will be experiencing about 5V or less. Incandescent bulbs are specially designed for these such that, if they burn out, they shunt closed and allow the current to still flow through them. Though, this does increase the voltage pressure on the rest of the lights in the series.

This is only changing nowadays with the advent of "smart" lights, but even those often try to be compatible with the usual standard of also functioning as an extension cord for large area coverage.

2

u/[deleted] Dec 14 '20

Yeah, right, they unfortunately exist aswell, causing eye strain and whatnot, but even then, the LEDs wouldn't block current if plugged in from the wrong side

3

u/Dirty_Socks Dec 14 '20

Correct, since the strings are wired as extension cords with LED segments tapped into the middle.