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NVR v. Start/Stop switch?


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Established Member
4 Sep 2005
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Miles away - totally impractical...
I'm trying to buy a new switch for my tablesaw (old one broken), and I'm a bit confused...

NVR switches
Since removing the old switch, I have discovered that I have a spare Brown wire (that used to go to a terminal on the old switch). It's not needed to power the machine, therefore, I am guessing that it must have a role to play with regard to the switching/safety - is this something to do with the NO VOLTs bit of the NVR???

START/STOP switches
I've tried using a couple of these - one was an old MEM switch that tripped via a heat triggered mechanism (if the saw load caused the amps to get high enough to cause sufficient heat in the switch, it would trip off); however, it could not cope with the power of the saw under normal running conditions. I then bought another MEM switch which seems to be electronically controlled and I'm figuring could be a NVR switch? No idea how to wire the thing up though, particularly as it caters for single and 3 phase :shock:

If there is anything that anyone can tell me to confirm my theories above or otherwise enlighten me, I would be ever so grateful!



Established Member
3 Sep 2005
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Co Down
The extra wire may be to allow an emergency stop button etc. to be wired into the system. If the switch has maker and id on it, then you could use google to see whether there is information available. Vendors such as RS Components put up lots of diagrams and information which can be easily accessed. They do an NVR switch for less than £10 and you can buy overload devices for around £4.