chris ma said:A I was going to install two of them per psu as a power switch. One switch for hot and one switch for nuetral. But I was lucky here that I mentioned it in this forum and got some quick messages from fellow members to warn me not to do it.
Do not do it this way, why? I don't recall now, but I trust my fellow members here so I just will not do such a thing and buy proper 2 poles power switches instead.
Chris
Hi there........
Standard AC house wiring practises in Europe stipulate the <hot wire > be the switched one in any installation. The neutral stays put if that is if supply is 0V or ground referenced. Take the example in a two-way domestic light switch.......you want to change the bulb; the wiring should be configured that no AC <live> appears on the bulb when either switch is switched off......(user safety)
If a double live is used i.e biphase AC 110V then things get more complicated.
In electronic equipment i.e amps and radio's using metal chassis with simple requirements, don't switch neutral with live connected........if the earth becomes duff and has Y caps connected with an input filter, then the chassis will become live. In this situation the electrocution danger is high if an earthed signal input cable (from another earthed equipment) is removed .....never rely on the possibility of the mains safety earth being connected to another equipment. Only if it is IEE double insulated classified then things are different. On alot of homemade botch-ups, it's suprising how much this is violated, esp in older equipment chassis.
Switching AC equipment feeds with double throw double toggle switch so both power inputs are fully disconnected at the same time is a sure way to save the day if the plug is manipulated or reversed. The earth contact should be the last to leave the equipment, and if cord is hardwired to chassis through a grommet....then the earth wire should be the longest .........Reason, on long extension leads (i.e stage work) if someone trips over the cord and yanks the hot and neutral out of the chassis wiring, the supply fuse will probably blow but again the earth wire should be the last to leave the chassis. Again, user safety reducing the chances of electrocution from a live chassis.
I take no liability over these revelations.....alot is CS. If in doubt see how it's done physically by an equipment/installation practitioner.
rich