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Looking to illuminate the underside of paper guillotine

Thanks for your reply. I'm looking at the diagram and what I've done and can't quite figure out what I need to change.

From what you have said, it sounds like I need to retain the original connection from the DC plug to the light, but then I don't know how the switches are incorporated.

At the moment, red wire goes from power to com switch 1, from com switch 1 to com switch 2 and then light. Black goes to nc switch 1, from nc switch 1 to nc switch 2 and then light.

One cable from power to switch 1, two cables from switch 1 to switch 2 and one cable from switch 2 to light.

Have I unnecessarily added two rather than one cable from switch to switch? Should I have two cables from power, with one black and red going straight to light and the other going to switch one then switch two? What then?
 
I just noticed the diagram has a plus and minus. So the minus represents the black cable, which goes straight from power to light negative, whilst red goes from power to switch 1 com, to switch 2 com and then light positive?

Then I'm lost? Add one more cable (red and black) and connect how?
 
Try this:
Power red to red on the switches,
Lamp red to black on the switches,
Black on lamp to power black.

ps. Leave both red and black linking the switches.
 
Thank you, I am sure this is really frustrating for you, I'm frustrated because it seemed so simple and now it seems so complicated. It's all in my head no doubt.

So...
Red = DC to Switch 1 (COM) to Switch 2 (COM)
Black = Lamp to DC
Mix = Lamp Red to Switch 2 (NC) Black

Is that right?

You say to leave the red and the black linking the switches.

At the moment, I have two cables going from switch 1 to switch 2. Is that necessary? If I remove one, does it work exactly the same? I added two because of the comment about running parallel.

Am I essentially missing one cable (so there should be three in total)?
 
Last edited:
I disconnected DC black from switch 1, light black from switch 2 and added a third black test cable. I connected light black to switch 2 NC.

The result was that the light is on either when the lock is engaged or the blade is not all the way down.

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I moved the black wires from NC to NO and now it's not taking into consideration whether the blade is fully down or not, it only factors in whether the blade is locked. So I guess one of the black wires needs to be on NC and one on NO. It's all very confusing.
 
I have now tried various different contact pairings and I cannot get it to function correctly. Having some red wires on NC and others on NO didn't have the desired outcome. Neither did switching each pair from NC to NO or the other way around. About the only thing I don't think I tried was changing the black light to DC cable, but I don't see how I could change that anyway.

I don't understand.
 
You should have only moved the wire on the lock switch, as I said? The blade one was already working correctly...
 
This is how it is currently operating:

Lock catch unlocked (touching microswitch), light on.
Whether the blade makes contact with the second microswitch makes no difference.

So it looks like the lock microswitch is working correctly and wired correctly.

So I tried moving the red wires on the blade microswitch from COM to NO. Made no difference, then again, I guess it shouldn't as I should be moving black wires? So is the problem that the black wires on the blade microswitch are connected to NC instead of NO?
 
Ah, that seems to be the answer after rewiring. Looks like I got confused about NC and NO on microswitch 2 because they are oriented differently.

Power circuit:
DC black to LED black (-)
DC red to microswitch 1 (COM)

Switch circuit:
2 x Microswitch 1 black (NO) to microswitch 2 black (NO)
2 x Microswitch 1 red (COM) to microswitch 2 red (COM)

Mix circuit:
Power LED red to microswitch 2 (NC)

Does that sound right? Does it need the two cables between the microswitches, or could I use one for the black cable only that goes from DC to LED?
 
You need one wire from switch 1 NC to switch 2 NC

Nothing on the NO contacts.
(And still keep one wire from switch 1 common to switch 2 common).

All the other connections look OK; the blade switch is not working as the LED is not connected to that, as the link between the switches is wrong.

The LED positive and the link should go to NC, so either switch connects power to it.
 

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