View Full Version : Wiring a On/Off Switch

11-06-2008, 09:19 AM
Well I've read a whole bunch of stuff and still none the wiser. There's smart people here, so I thought I would ask :grin:.

I have some nice little on/off switch/socket/fuse combo that I bought from Jaycar a few weeks ago to use with my 2 transformers. Proud of myself that I was being oh so safe, I got home and actually looked at it and went "oh phooy, I've got to wire it up myself". So I need to learn how to connect power in, the fuse and the switch and what order to do it in (no point in wiring it up the wrong way and have the fuse redundant in some way).

Was going to have a crack at it myself, but I'd rather not since I'm not totally 100%. If someone here could explain the how and the why, that would be fantastic. I know the usual disclaimers apply, if I mess up, it's not your fault, blah blah.

Thanks heaps.

11-06-2008, 09:26 AM
Using the picture of the back of the switch, here's how you'd want to wire it. Also note, that the best way to do this would be to use those crimp spade terminals, so you can just slip them on, rather than having to solder to the posts.

You'll notice the top-most connection on the left goes to one leg of the fuse in the center. The other terminal in the center at the bottom should go to your switch (more on this later). The left center terminal would be your equivalent to ground, so connect any grounds to that. And the left bottom would be your neutral, so connect your neutrals to that.

As for the switch.... you'll need to determine which pair of terminals is what. Use your multimeter to check continuity as you turn the switch on and off, that'll tell you which ones go together. But anyways- bring from the center terminal to one side of your switch, and then the other side of your switch would be your switched power leg.

So there you have it, power, ground and neutrals. I'm hoping that was clear enough.

**edit: looks like for the switch that the 2 upper terminals are together, and the 2 lower terminals are together. So your middle terminal goes to the top of the switch side, and then the bottom of the switch side is your power out. You have 2 terminals because it is a double pole switch. (DPDT). Just make sure if you connect to the left terminal on the top, you connect your power out to the left terminal on the bottom.

11-07-2008, 05:49 AM
this is all i can tell you

11-10-2008, 02:11 AM
bump if you didnt see it ingrid

11-11-2008, 05:38 PM
I'm so sorry - thank you for the answers.

Once I had the answer I had full intention of wiring the switch . . . . but then got distracted and finished something else off instead. I have every intention of wiring up the transformers tonight, so I'll post to make sure I've got it right and not ripping a hole in time and space ;)

11-12-2008, 08:23 AM
Ok, so here's how I've interpreted instruction . . . . .

Earth was easy - I'm mounting on a wood board, so nothing to really earth to. Measured the switch in the ON position and the two top and two bottom pins match - that's left matches top to bottom and right matches top to bottom. So reading the instruction, this is what I came up with.

Green - earth . . . . no point in really doing anything, I just thought I'd mark it to remind me where it was.
Red and blue - easy enough to see where it's wired.
Pink - to the transformer, in actuality they're both orange leads to the transformer, and neither one is marked - or +, so I take it that it doesn't matter which one goes to what.

Any good or kablamo? Edit for anyone reading this - keep reading, this is totally how NOT to wire the switch. I'll leave the pic here to clarify why it's wrong.

11-12-2008, 09:05 AM

That circuit does not look right. By matching, I take it you mean continuity (zero ohms) between top left-bottom left and also between top right-bottom right.


11-12-2008, 09:35 AM
Huh? See this is why I like MS Paint - saves me effort. Anyone care to cut to the chase and just draw it? Might make the explaination a little clearer (for little old me).

11-12-2008, 09:40 AM

I can draw it up, if you confirm that the circuit continuity is vertical, top left to bottom left etc otherwise it will go bang.


11-12-2008, 09:49 AM
yup - top left to bottom left.
Thanks :grin:

11-12-2008, 09:54 AM
OK, try this.

11-12-2008, 10:12 AM
Thanks prof (and Tim in chat). I'll have a crack at it tomorrow (well tonight now ;) ) and see how I go - picture helps dummy here lots :)

11-12-2008, 09:10 PM
Thanks prof (and Tim in chat). I'll have a crack at it tomorrow (well tonight now ;) ) and see how I go - picture helps dummy here lots :)

you only have to run live through switch cause without live it will not work so try that rather than run 2 as you could destroy your transfromer which wouldnt be a good i dea i wouldnt want to see that happen

11-13-2008, 04:59 AM
switching active and neutral through a double pole switch is actually quite a good idea. that way if the polarity is reversed on the plug top or input source the active will still be isolated when the switch is off..

05-31-2009, 05:53 AM
opening this post up again for a quick and easy question, what kind of fuses did you use int he switch Ingrid?bought a dozen of ebay for my toroidals and power supplys to make them safer
Ta Synnie

05-31-2009, 07:17 AM
After all that I was *cough* naughty and didn't use them . . . . In my defense I ran out of time and just bunged it all together, flicked the switch and prayed to God, Allah and Buddha (covered my bases).

I just went out to have a look and see what I bought and I can't find them. I just went into Jaycar and said "something for mains power please". I don't think they were anything special or cost any more than a few cents.

Sorry that's not very helpful . . . . . :(

06-01-2009, 02:17 AM
OOPS TP, ok we wont say nothing to loud in case someone hears us....mine didnt come with a fuse so ill look on jaycar and see what they have to offer
Cheers Synnie