Hi there, I'm new to this forum, so hello. I have a quick question, I'm in the UK by the way: I am making a pedal switch for a friend for his router to make life easier. I got a footwsitch off of ebay a while ago, the actual switch inside is rated for 15A and 250V so should be fine for UK power. So What I have done is make up a short extension cable, just 1 meter and in the middle of the cable, I've just cut the live wire put cable into junction box, and off the now two ends of the live added the cable that just goes to the push to make switch.

Do I need a capacitor across that switch to smooth the power delivery or does it not matter that much with power tools. If so, what type of capacitor and rating would be the best to use?

 

hi iFunk,
Welcome to AAC.
You could connect a 'snubber' across the switch contacts.
That is a 100 Ohm resister in series with a 100nF capacitor.
It is important that the capacitor is suitable for mains operation.
E

 

Hi ericgibbs, thanks for your reply, thank you, new word 'snubber' was exactly what I needed, that's awesome, just found lots of info on that, thanks very much.

 

hi,
You can buy snubbers in one plastic moulding, includes the resistor and cap.
E

 

I'm in the UK by the way: So What I have done is make up a short extension cable, just 1 meter and in the middle of the cable, I've just cut the live wire put cable into junction box, and off the now two ends of the live added the cable that just goes to the push to make switch.

Don't forget the earth wire to the foot pedal frame if metallic cover/case.
Max.

 

A snubber is an OK idea but probably not a requirement.

 

Ah ok, so considering that I am using a push to make switch, not a toggle on off switch. Basically my friend does wood work and so the router that he uses has a switch in an awkward position, so he will be switching it on, then using the footswitch to take the power from the mains. Do you think it's ok without? It won't shorten the life of the router? for me it's a lot easier without, but I'm new to power electronics really.

 

Don't forget the earth wire to the foot pedal frame if metallic cover/case.
Max.

Thanks for that, that was something I didn't think about, it is indeed a metal foot switch.

 

Do you think it's ok without? It won't shorten the life of the router? .

A snubber across the switch is more for it than the router, there can be quite the arc when breaking motor loads such as these, if you can fit it in, it may save the switch from premature failure.
Max.

 

I think I'd like to put one in, I have a junction box that takes the live feed from the extension cable so there is plenty of space. Thank you all for you help, this is an awesome forum!

 

So I have a snubber component, but data sheet doesn't tell polarity, how can I check this so i don't blow the cap in it? I have included the datasheet the one I have is the bottom one.

 

hi,
It really doesn't matter, but conventionally the resistor end is connected to the Live wire.
E

 

Yes, I would have expected the resistor part first, the problem is there is nothing on the component or in the data sheet to show which way round it is, is this just a bad data sheet or is it because the component is not polarised? If it is how could I test it to see which lead is attached to what?

 

Its not polarised, so its orientation does not matter.
Most times if you read a circuit diagram the resistor would be connected to live.
Just convention.
E

 

Of course it's not, we are talking AC not DC current aren't we.