Jet JWL 1220 on off switch not working

Rodpr · 30 May 2023

I went to turn a tool handle and my lathe just won't stay on! I have a Jet JWL 1220 (not the variable speed model) and I have been very happy with it but now it won't stay on. It has the two button switch (green 'on' above red 'off') and it runs when I press the green button but stops as soon as I let go.

Is this likely to be a worn out switch? Any ideas whether it can be repaired or replaced? I have seen 'on/off' switches purportedly for this lathe on US sites but it is just a very standard toggle switch, not push buttons.

Has anyone had a similar problem?

Many thanks,

Rod

Linus · 30 May 2023

The switch should be a NVR type and when you push the green "on" a relay engages holding the machine on whilst power is present. If the relay fails or has dirty contacts then the machine will switch off as it should do for safety. That would be my first item to check. Perhaps someone with the same machine can confirm the type?

Rodpr · 30 May 2023

Thanks Linus. I thought it would probably be a dust problem. I will start taking things apart (after unplugging!)

Rodpr · 30 May 2023

I took out the switch. Took it apart, cleaned up contacts and put it back again. Same problem. So I have ordered a new one (Kedu KJD 20-2). Hope I can remember which wire goes where!

Linus · 30 May 2023

The secret is to take a photo before disconnecting

Looks like a standard NVR switch and normally the wiring diagram is shown on the side. There was a similar post previously concerning this problem.

https://www.ukworkshop.co.uk/threads/help-new-nvr-switch-does-not-stay-on.130328/

okeydokey · 31 May 2023

Linus said:
The secret is to take a photo before disconnecting Looks like a standard NVR switch and normally the wiring diagram is shown on the side. There was a similar post previously concerning this problem.

https://www.ukworkshop.co.uk/threads/help-new-nvr-switch-does-not-stay-on.130328/

Sometimes the shape of how the wires have been previously been connected will guide you to where they connect if you simply hold the new switch close to the wires

Rodpr · 2 Jun 2023

New switch arrived, wiring is pretty straightforward, two from mains supply at bottom and two to motor at top. I was able to check which connections were which by jiggling the cables. All sorted and working perfectly! I celebrated by making some knobs for the lathe on the lathe!