raumfahrtagentur

1.11.2022 03:29:10
Well, if something is stupid but works, it isn't stupid.

1.11.2022 21:13:47
I second that fully!
But: do you refer to that data recovery approach? Wouldn't consider it stupid. ;)

16.10.2022 12:22:00
somebody explain this to me plz

18.10.2022 01:16:04
stay tuned.. preparing a longer answer

19.10.2022 22:05:47
Pictured is a mains power distribution box w/ plugs in it, and a heater, a protective earth contact (PE; don't mix up with 'potential equalization' though it can be used in the same realm) of the distributor plug bar is somewhat connected to a heating pipe with a kind of loudspeaker twin cable or simple low-voltage DC twin cable.

This is simply wrong in so many ways... idk where to start (don't know your bg, so some generic explanations included)
* PE serves to protect biological beings from electric shock in case of touching e.g. parts of a metallic enclosure of an elec. device where a faulty power line went off its destination and connects to that metal enclosure. In this case, the electric energy is directly sent to ground (earth) and thus preventing it from flowing through a Lebewesen ,)
* PE shall be connected with reasonable screws to the potential equalization bus bar in the house's foundation, a solid metal bar going down to earth
* the PE of your distribution board is also connected to that PE bus bar in the basement
* each individual PE of a e.g. power socket goes to the PE in the distribution board (or a sub distributor box w/ own PE), so it always shall form a star towards the main distribution board, which then has the thickest PE wire to the main PE in the base
* the house heating installation has to be grounded (aka connected to principal PE) with a reasonable thick conductor
* in case the heating installation is based on any gas in a pipe coming from outside the house, this gas tube must also get grounded outside the house (to prevent an electr. current flowing through that tube in case of a lightning strike)
* the two conductors of the used twin cable are twisted to each other on stripped ends . This does not automatically forms a conductor with twice the diameter of a single cable, as you never know how good the interconnections on both ends are in the end. Don't ever think of soldering here...

Main question here remains why this 'installation' has been made at all.

* lots of people are able to feel that certain 50 or 60 Hz hum when touching metal surfaces of powered devices. This AC voltage (usually well below 50V) is not dangerous as only tiny currents flow, but must be observed because it can 'develop'. Never use electrical appliances w/ high amperage on extension lines, use wall sockets - their PE has much lower ohmic resistance (and hence, in an AC circuit, much lower impedance) to allow an error current propagate faster to sink to PE). - So if that was the reason to attach this wire: start with replacing the extension line, if this does not work out, call an electrician
* in an ideal world and in good installations, there is no voltage potential between different PE terminals, and hence no current flowing through
* connecting PE in a mesh like pictured, voids the star topology; a RCD (german: FI) might or will fail
* PE always must have at least the same wire diameter as phase and neutral connectors have (wider is better, but never less diameter than Lx and N). The reason for that is: in case PE is really needed, it shall burn as the last cable, if ever
* if current flow trought this wire, corrosion esp. in the heating installation will occur
* these contructs lead to a false sense of security which won't pay back when required, but the opposite
* your insurance company will not pay for the mess

Most installation here (looks like Germany) use a TN-C-S power distribution (https://de.wikipedia.org/wiki/TN-System#TN-C-S-System), a break in the PE wire will then sink an error current trough N, which can lead to other damages.

Remember: electrical power has no friends. It'll unconditionally kill you, your friends and enemies, if handled inappropriate.

Be careful when doing stupid things! https://kyselo.eu/raumfahrtagentur/post/27392

20.10.2022 13:48:05
that was an impressive answer. possibly the longest comment in the history of kyselo, right @admin ?

22.10.2022 02:18:55
well... tnx, @looque ; you asked for explanation ;)

8.11.2022 00:37:50
@looque yes, it is longest comment ever :-D