Can I just swap out my old stop button without changing the cable or does it require the new cable? I think the answer is use new cable else why would they send it.. But I have to ask due to a full area under my machine. Also are the EX and AUX boxes supposed to be mounted back to back? I may have to extend my electronics mounting bar.
You’re talking about the E Stop button? existing cable should be fine, however that new cable is to connect the E Stop port from EX to the Aux box, and then you connect the E stop to the aux box. It’s important to follow the setup instructions on this properly or you could end up in a state where your main controller works but your aux box is in permanently E stopped.
I just installed my new E-Stop button last night. I noticed however that my existing E-Stop button was identical to the new one, same part numbers on the switches. I’m hoping the new one I got is correct.
They’re different internally, the new ones are double pole, old ones are single pole. Crack open the old one and you’ll only see one switch, the new one will have two. Those part numbers are just for the outer enclosure.
They both have 2 switches in them and the part numbers on the internal switches are identical. They are identical inside. I got my original machine in early 2025, maybe they were shipping double pole stop switches at the time
I thought I’d seen some photos of the two recently, but haven’t been able to find the thread. I was going to reference them but the guts inside the box of both switch assemblies are the same.
Ahh, they did start switching those a bit ahead of time. Forgot about that
Can you wire up 2 E Stops in parallel?
I don’t know if Avid does it this way, but in general… no. Estops are wired in series. Each estop is normally closed and the string of estops powers the main contactors or something. If any estop is hit, it opens the circuit and the main contactors shut off, killing power to everything.
The second set of contacts in an estop is typically used as a signal to the computer to tell the operator which estop is tripped.
On my setup (linuxcnc) the estops are wired as above, and in addition, each contactor powered by the estop chain also has a relay on it, so the computer can individually control each contactor yet allow the estops to override it.
So: +24v → estop → estop → estop ->(*)-> contactor-> relay → GND
Each contactor (left of (*) is shared, right of (*) is per-contactor) will only be on if all the estops and the software agree that they can be on.
The above setup also means that a broken estop wire kills everything, and a short to ground should trip the power supply’s overcurrent sensor and kill everything.
Thanks for the information.
I should have just asked if 2 Estops can be wired in and if so how.
Also, this is my very minimal safety speech to visitors: “This is the emergency stop. There’s another one over there. If there’s an emergency - someone is getting hurt or the machine is on fire - hit the estop. Don’t worry about breaking it, you can hit it as hard as you like. There is no penalty for hitting it if you need to, or hit it by accident, but if you just want to stop the machine to change something, please tap the escape key instead.”
If the Avid box has multiple estop connections, use those 
If not, and you really want to, you need to understand the internal wiring so you can wire the normally closed contacts in series but the normally open ones in parallel.
Perhaps Avid should sell an “estop splitter” that does the right series/parallel for their estop cables 
Our E Stops send a signal to the control, and dump power to the motors and spindle.
They can be wired in series, we sell “pass through” e stops so you can hook a bunch up in a chain. If anyone of them is pressed, the machine stops.
I don’t believe the pass through E Stops are advertised on the site, but if you contact support they can get you one. They’re easy to hook up: There are M12 connectors on either side of them.
I would like to splice a 4 pin XLR style male/female connector into my m12 estop cable to act as quick connect/disconnect. My control computer is on an enclosed mobile cart 10’ away from were my control boxes are and I run an ethernet cable over to it only when running my machine. I want to mount my E stop to the same cart so it is more accessible to where I will actually be standing when my machine is running. Is there any reason this would be considered a bad idea?
All of your E stops need to be wired in series so that if the “loop” breaks your E stop is triggered. By design a disconnect-able E stop wouldn’t work because it would allow you to have an E stop which might not necessarily do it’s job visible.
Best thing to do is just get two buttons, wire them in series (or get the kit from us) and have buttons in whichever two places you want
So are you saying that you have a two button kit so you can have an e-stop located on each side of the CNC
But if that is the only button available and it isn’t hooked up the machine won’t even run, correct? I was avoiding the idea of adding a second button because of the very thing your warned against, a visible button that may not be connected. Right now my e stop is mounted next to my control boxes on the wall next to my machine and it’s perfectly easy to get to but, in the event of an emergency, I would have to walk around my machine to press it.
Think of it like this:
1 e stop button as a loop of wire in it. When that loop of wire gets broken the machine E stops.
Unplugging the E stop or pressing the button breaks the loop.
“pass through” E stops from us extend that loop, but keep in mind there’s only 1 loop. So you could have 17 E stops plugged into that loop, and if any one of them is unplugged or pressed the machine will be in E stop.
So in that scenario each of those 17 E stops would be plugged into the last one, just like christmas lights.