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Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Tue Oct 26, 2021 8:12 pm
by CivilCNC
Hello im wondering if I can run two estops circuits. one Normally closed, and one Normally Open.

Why would I want to do this? Well because my Novakon Torus pro came with two estop circuits, one NC as a "hard estop" that shut down the servo motors, and a NO estop that was more of a "soft estop" that would trip when the electronic power drawbar malfunctioned.

Thanks
Jake

Re: Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Tue Oct 26, 2021 8:26 pm
by Upnorth
This is easy to do. Your soft stop will be connected to the acorn. For the hard stop you can interrupt the power to the servo drives. Put a switch or relay that will cut off power to the drives when you push the red buttons. Read the manual for your drive to see where it is safe to interrupt the power in the circuit. S I use estops (big red button) that I buy at the local electrical supply house. If I remember right the ones I use can have anywhere from 1 to 9 sets of contacts on them. They are modular and you can configure them any way you want. There are normally open and normally closed contacts.

Re: Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Tue Oct 26, 2021 8:33 pm
by CivilCNC
Upnorth wrote: Tue Oct 26, 2021 8:26 pm This is easy to do. Your soft stop will be connected to the acorn. For the hard stop you can interrupt the power to the servo drives. Put a switch or relay that will cut off power to the drives when you push the red buttons. Read the manual for your drive to see where it is safe to interrupt the power in the circuit. S I use estops (big red button) that I buy at the local electrical supply house. If I remember right the ones I use can have anywhere from 1 to 9 sets of contacts on them. They are modular and you can configure them any way you want. There are normally open and normally closed contacts.
excellent. I like it. Thanks!!

Re: Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Tue Oct 26, 2021 8:38 pm
by CivilCNC
Upnorth wrote: Tue Oct 26, 2021 8:26 pm This is easy to do. Your soft stop will be connected to the acorn. For the hard stop you can interrupt the power to the servo drives. Put a switch or relay that will cut off power to the drives when you push the red buttons. Read the manual for your drive to see where it is safe to interrupt the power in the circuit. S I use estops (big red button) that I buy at the local electrical supply house. If I remember right the ones I use can have anywhere from 1 to 9 sets of contacts on them. They are modular and you can configure them any way you want. There are normally open and normally closed contacts.
One more question, I suppose on both estop circuit it doesnt matter what wire goes to where? as long as the circuit is complete and it is setup as normally open, or normally closed? Like I cant get them backwards.. is what I mean.

Thanks
jake

Re: Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Tue Oct 26, 2021 8:45 pm
by Upnorth
Correct they are like a normal switch with a single set of contacts.

If you do set up the estop to cut off power to a 220VAC circuit though make sure you use 2 sets of contacts so you can break both L1 and L2. Cutting off only 1 can leave a half live circuit.

Re: Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Tue Oct 26, 2021 8:49 pm
by CivilCNC
Upnorth wrote: Tue Oct 26, 2021 8:45 pm Correct they are like a normal switch with a single set of contacts.

If you do set up the estop to cut off power to a 220VAC circuit though make sure you use 2 sets of contacts so you can break both L1 and L2. Cutting off only 1 can leave a half live circuit.
Awesome. I was thinking I would run the hard estop to the relay at the bottom din rail in the Novakon cabinet. It was a 12v from the Novakon BOB but I switched it to 24v since the acorn is 24v signal to turn on the servos with that relay.

Re: Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Wed Oct 27, 2021 12:24 am
by CivilCNC
CivilCNC wrote: Tue Oct 26, 2021 8:33 pm
Upnorth wrote: Tue Oct 26, 2021 8:26 pm This is easy to do. Your soft stop will be connected to the acorn. For the hard stop you can interrupt the power to the servo drives. Put a switch or relay that will cut off power to the drives when you push the red buttons. Read the manual for your drive to see where it is safe to interrupt the power in the circuit. S I use estops (big red button) that I buy at the local electrical supply house. If I remember right the ones I use can have anywhere from 1 to 9 sets of contacts on them. They are modular and you can configure them any way you want. There are normally open and normally closed contacts.
Something I was thinking of, is that Acorn won't recognize the hard estop as an estop at all if it doesn't have a signal to the input. It will just shut shut servos off, not put the machine in an estop condition.

So I may just not use the novakons original soft estops similar to what you did.

Re: Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Wed Oct 27, 2021 4:54 am
by Upnorth
The novakons original soft stop goes to the breakout board. You can hook it up to an acorn input and configure it as an estop in the wizard. This will cease all outputs to the servo drives instantly. Cutting off the power to the servos is the secondary safety function and makes 100% sure motion stops. Initially I did not have a hard stop and the acorn worked fine but I added the hard stop later for safety reasons.

Re: Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Wed Oct 27, 2021 11:05 am
by CivilCNC
Upnorth wrote: Wed Oct 27, 2021 4:54 am The novakons original soft stop goes to the breakout board. You can hook it up to an acorn input and configure it as an estop in the wizard. This will cease all outputs to the servo drives instantly. Cutting off the power to the servos is the secondary safety function and makes 100% sure motion stops. Initially I did not have a hard stop and the acorn worked fine but I added the hard stop later for safety reasons.
Yes I just want this to be aa safe as possible. I plan to add the MPG as well, and I want that to be a hard stop to turn off servos. I wonder if this will cause any issues? It'd be easy enough to swap estop circuits worst case

Re: Two E-Stops? One NC and one NO? Novakon Torus Pro PDB

Posted: Wed Oct 27, 2021 1:14 pm
by Upnorth
I have the acorn MPG. It does not have an EStop on it like my previous Mach 3 mpg did. My Novakon mill came with a estop that is magnetically attached to the front of the drip pan. Did yours come with one? I think it's better than one on the mpg. I can hit it far faster than fumbling to grab for a button on an mpg.