3 ms·

There's a terrifying teardown of one of those heated shower heads here: https://hackaday.com/2018/08/25/electric-shower-head-tear-down-makes-us-wince/ https://

by tyingq 4y ago

There's a terrifying teardown of one of those heated shower heads here: https://hackaday.com/2018/08/25/electric-shower-head-tear-down-makes-us-wince/ https://hackaday.com/2018/08/25/electric-shower-head-tear-do... When he opens it, the ground wire is just floating in the enclosure, not hooked up to anything. Contacts that would mechanically fail to shorted, etc. He also mentions it flows ~24 amps of 220V on the high setting.

mmastrac 4y ago
> The green wire which is a neutral has no place to fasten inside the plastic body. It just goes inside, connects to nothing, while being exposed in the path of the water, presumably to keep water that was too conductive from shocking you I have nothing to say to this. Wow.
- Scoundreller 4y ago
  Maybe I’m dumb but what else would the ground on a completely plastic enclosure be connected to?
  - tyingq 4y ago
    The ground wire is floating in an area that would have water in it, sometimes being electrically connected to the water, sometimes not, depending on the flow, how the wire is bent, etc. He measures leaking voltage to the pipe and the water and gets readings. There are actual safe inline electric water heaters with inbuilt GFCI, proper grounding, probably other protective circuits, etc.
Shorel 4y ago
I used them for over 20 years in South America. I even burned them many times, to the dismay of my dad. I burned them because I wanted hotter water, and closed the water line as much as I can, the resistance heated up to red and then melted. The fact that ground contacts the water is by design. As far as I know, no one has ever been electrocuted by using one of these showers, not even me, so used to burn them. The only reason I use gas heaters now is: I can shower with hot enough water for a long time. So that teardown can be terrifying to you, but millions of South Americans pay no attention to such fear mongering at all. They are safe for people.
- stickfigure 4y ago
  I can confirm these are universal in Central America. It always terrified me somewhat, especially the more janky looking installs.
- xani_ 4y ago
  I mean, sure, you can make them work, but this particular one wasn't done correctly > I even burned them many times, to the dismay of my dad. I burned them because I wanted hotter water, and closed the water line as much as I can, the resistance heated up to red and then melted. I'd imagine making one with PTC (element that decreases resistance when heated, self-regulating temperature) would prevent that but that would add a buck or two on material bill
- tyingq 4y ago
  I believe you that accidents don't happen often with them. But, on the other hand, you're describing a scenario where you: - Melted the enclosure, probably exposing the wiring, maybe near your hand if you reached up to see what was happening - While you might have been standing on a drain that was an excellent path to ground And, if the ground wire is meant to be constantly in contact with the water, there's certainly cheap ways to ensure that, that are better than "exposed stripped end randomly sits in the chamber".
  - Shorel 4y ago
    The enclosure doesn't melt. The resistance splits, and no longer provides a path for electricity to flow, so it stops heating. No wires are exposed. It's similar to an old electric bulb failure.
kwhitefoot 4y ago
Electroboom did a video on the subject. It seems that they are actually safe. Not sure I'd be willing to try it though. https://www.youtube.com/watch?v=06w3-l1AzFk https://www.youtube.com/watch?v=06w3-l1AzFk And bigClive https://www.youtube.com/watch?v=cNjA0aee07k https://www.youtube.com/watch?v=cNjA0aee07k diodeGoneWild https://www.youtube.com/watch?v=jo99U3nVCnA https://www.youtube.com/watch?v=jo99U3nVCnA

by tyingq 4y ago

mmastrac 4y ago

> The green wire which is a neutral has no place to fasten inside the plastic body. It just goes inside, connects to nothing, while being exposed in the path of the water, presumably to keep water that was too conductive from shocking you I have nothing to say to this. Wow.

Scoundreller 4y ago
Maybe I’m dumb but what else would the ground on a completely plastic enclosure be connected to?
- tyingq 4y ago
  The ground wire is floating in an area that would have water in it, sometimes being electrically connected to the water, sometimes not, depending on the flow, how the wire is bent, etc. He measures leaking voltage to the pipe and the water and gets readings. There are actual safe inline electric water heaters with inbuilt GFCI, proper grounding, probably other protective circuits, etc.

Shorel 4y ago

I used them for over 20 years in South America. I even burned them many times, to the dismay of my dad. I burned them because I wanted hotter water, and closed the water line as much as I can, the resistance heated up to red and then melted. The fact that ground contacts the water is by design. As far as I know, no one has ever been electrocuted by using one of these showers, not even me, so used to burn them. The only reason I use gas heaters now is: I can shower with hot enough water for a long time. So that teardown can be terrifying to you, but millions of South Americans pay no attention to such fear mongering at all. They are safe for people.

stickfigure 4y ago
I can confirm these are universal in Central America. It always terrified me somewhat, especially the more janky looking installs.
xani_ 4y ago
I mean, sure, you can make them work, but this particular one wasn't done correctly > I even burned them many times, to the dismay of my dad. I burned them because I wanted hotter water, and closed the water line as much as I can, the resistance heated up to red and then melted. I'd imagine making one with PTC (element that decreases resistance when heated, self-regulating temperature) would prevent that but that would add a buck or two on material bill
tyingq 4y ago
I believe you that accidents don't happen often with them. But, on the other hand, you're describing a scenario where you: - Melted the enclosure, probably exposing the wiring, maybe near your hand if you reached up to see what was happening - While you might have been standing on a drain that was an excellent path to ground And, if the ground wire is meant to be constantly in contact with the water, there's certainly cheap ways to ensure that, that are better than "exposed stripped end randomly sits in the chamber".
- Shorel 4y ago
  The enclosure doesn't melt. The resistance splits, and no longer provides a path for electricity to flow, so it stops heating. No wires are exposed. It's similar to an old electric bulb failure.

kwhitefoot 4y ago

Electroboom did a video on the subject. It seems that they are actually safe. Not sure I'd be willing to try it though. https://www.youtube.com/watch?v=06w3-l1AzFk https://www.youtube.com/watch?v=06w3-l1AzFk And bigClive https://www.youtube.com/watch?v=cNjA0aee07k https://www.youtube.com/watch?v=cNjA0aee07k diodeGoneWild https://www.youtube.com/watch?v=jo99U3nVCnA https://www.youtube.com/watch?v=jo99U3nVCnA