Hi i want to fit a switch to my psu so can isolate the power without having to unplug the cable or reach behind me desk for the mains. lookin on maplins i have found a rocker switch which says 16A@240v which i think is right but there are a few different vairants with spst, spdt, dpst and dpdt. now which one do i need? and which wires do i need to cut? tia d
You'll need a DSPT. It will have 4 contacts, and as long as you don't put the two AC lines into a position where they'll short each other out, it doesn't matter where you put 'em (if you don't have a multimeter to test for continuity, read my sig). There's a change that the color of wires inside your PSU will vary, but it's easy to check which lines are the AC lines because they're the power connector to the PSU has the pins in this config: Code: AC | | AC | Ground Take the two AC lines. If you only take one, the power supply will probably still be on, but quite angry at you (of course, I'm assuming that the PSU is a full-wave rectification device), and it will DEFINITELy be mad at you if you take the ground line away, so make sure to get both. edit: oh yeah, 16A@240v is definitely enough. My 400 watter takes in 5A@220v, and it's safe to assume you don't have a 1280w power supply.
I don't know much about UK mains voltage (as far as the phasing of the mains power), but if it is single phase, you can just switch the hot wire.
