UKC

https://1drv.ms/u/s!ApfLthxq63KJg8UIw9Fcjkv96y3SSw?e=Em9NTg

Trying to replace the switch on wifes hairdryer, the original was a 3 position slider - this is the photo of it

Id like to replace it with a rocker switch (3 position 6 pole). 

Ive managed to get it so its on full power, all good, but I dont understand the half power connection. Can anybody clarify this for me please?

It looks to me like the yellow thing with white wires is a EMI suppressor permanently connected between live and neutral.

On full power the black and blue motor wires are connected to live ( probably heat + motor).

On half power just the yellow wire is connected to live, the others are left open.

exactly my thinking, however translating that to a 6 pole switch has me baffled. 

Couldn't she just hold it further away? 

Can you post a picture of your 6 pole switch?

It's like this jobbie 

https://www.amazon.co.uk/Taiss-Position-（Quality-Assurance-YearsA...

Firstly, a bit of pedantry. This is UKC after all, and I'd hate someone to beat me to it. That's not a 6 pole switch. It's a 2 pole switch, it has 6 terminals.

It'll do the job. Connect the brown live wire to both of the two middle terminals. Connect black and blue to each of the top two terminals. Connect yellow to either of the bottom two. This switch will be off in the middle position, switch one way for full power and the other way for half.

Ah yes that's the correct terminology

What about the white?

The way I've got it wired now is using only one pair of each terminal 

II Blue+black

0 brown+white

I yellow

But this gives full power on both I and II, so you think it'll work if I seperate the blue and black and link the other two pairs?

I'm not sure what you mean, but it sounds like you have blue and black on the same terminal? If so, that's the problem. They are separate on the original switch, and there is a reason for that.

Use the old switch as a guide (ignore the bottom two unused terminals) and wire the new one the same. Connect black to top left, blue to top right. Connect brown to middle right, white to middle left. Make a short wire link between middle left and middle right (between brown and white). Connect yellow to bottom left.

Does it actually have a half power setting or was it cold-blow/hot-blow/off? It looks to me like it's probably wired for that though I suppose one of two heaters could be in series with the motor for warm-blow.

It looks to me like a single pole, double throw switch with a center-off position (or SP3T if easier to find, treat one of the positions as off by wiring nothing to it) switch would do. I think the one you have is double pole for manufacturing simplicity if it actually is at all. Wire the live to the common (usually center terminal) yellow to another, black&blue to the final one. Make sure it's rated to handle 240Vac and the fuse current.

There's not much can go wrong with a switch like that that can't be fixed with a bit of alcohol and emery paper.

edit: just read you have a new switch that isn't working right, seems the blue and black are split for some good reason that's escaping me at the moment. Wire your new switch exactly like the old one and it should work.

jk

Well it works! I still dont understand why but it does so I guess thats a partial success.

Thanks for your assistance.

It's a guess having never looked to see how a hair drier is wired but I suspect the yellow powers the motor via a second small heater for reduced heat and reduced blow, if you don't split the blue/black you get both heaters on and very little motor power so it runs hot.

jk

Well, if the aim was to get the hairdryer working then I'd consider it a total success! If the aim was to understand how it works, then that's a different challenge...

The motor has two wires coming from it, one for low power and one for high. Yellow is the low power one, and for this explanation we'll assume blue is high. The motor will have a single winding with three connections to it - neutral, half way along (yellow), and full (blue). When you connect yellow to live, it will run at half power, but blue will end up being live too because the winding will have a low resistance. If you've connected blue and black together this voltage appearing on blue will make black live too. This will power the heater, but also draw current through the other half of the motor winding (from yellow to blue), making it run at nearly full speed. This is why the switch is wired so that blue and black are switched separately.