I was curious if a 2nd (or 3rd) E-stop can be added into the wiring of the SLB or SLB-Ext and retain all expected functionality?
My use case is, I setup my AltMill per the instructions which has my SLB-EXT and E-Stop on the left-side (front?) which is not really my operating angle. I can safely reach it but ideally I have one on the other side that I can reach if on that side of my workspace.
Today I had my first major issue where my workpiece came loose from the double-sided tape and was spinning wildly around. I was on the right-side of the table at the time and had to travel to the left-front to E-stop.
Hey Corey,
As far as I know the e-stop is a normaly closed switch when released, meaning it shorts two wires towards the SLB. You can add switches to one of these wires, being it e-stop kinda switches with turn release option or even simple light switches, in line (serial) with the e-stop switch.
You can add as much if you like, but keep in mind that all these switches will need to switch into nc before the SLB gets out of e-stop.
I have my complete setup powered via a light switch located in my office for when things get spun around and I like to not go towards the action. I now can get myself into safety and be able to kill the death trap that is an out of control cnc.
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I think that’s a great idea and thanks for the information & image. It definitely opens up the potential options.
I’d prefer to use another Sienci E-stop (aesthetics) and mount to the other side but am open to other ideas. Safety is the ultimate goal but would be nice if it matched and retained the 3 action buttons as well.
Not sure if I need to contact support for the Sienci option. Not seeing the E-stop offered individually on the Store nor sure if it would extend the action buttons.
In theory, the E-stop wire would need to be in series but the Action/24V/GND wires could be parallel I would think.
I don’t see any problems with connecting the rest paralel. There’s not much going on except for some pulling up or down the tree button lines. But… if you are going to contact sienci for extra e-stops, it might be a good idea to enquire how much switch lights can be added to the 24v line. I can imagine too much amps out of that line might be potential damaging for the components switching that line. There might be not much wiggle room, risking a puff of smoke.
Have gone into the schematics and found the 24V power for the switch led is pretty much the same line that powers the motors. Should be oke to draw a few more switch leds on.
Full schematics for SLB are found here:
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Yeah, I’ll reach out to be sure but worst case, I can disconnect the 3 buttons on the primary (left) and leave connected for the alternate placement since the one on the left is awkward at best to use anyway. The E-stop itself is accessible but the buttons not as much in my setup.
I mean I can always relocated the one I suppose as well but I prefer options 
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None of this is officially tested and we probably don’t have time right now to test with the holiday season in swing, but from the conversation happening it all sounds doable to me 
Series E-stop, parallel all others, swap parallel connections to other E-stop if the lines become too long or you’re getting other unreliabilities. I’m sure it’d be fine to buy another E-stop from us and splice it in
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Thanks Chris - Your response was much more positive than Stephanie’s from Support - officially not offered or recommended is how I would summarize it (nothing mean meant by that).
I think it would be worth testing, when time permits. I’m not necessarily in any hurry.
Yeah fair enough response from her, we have no docs or testing on it and she doesn’t want to mislead people. If you asked me something like this about something I was less familiar with I’d probably respond the same but the SLB has been my project from the start so I’m much more familiar with it
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Oh I understand
Hopefully there will be time someday for some testing on this - I’m sure some people have already experimented as well, if not on the SLB then on the LB.
I may tinker at some point as well. Worst case, may just relocate the 1 E-Stop but as I think I mentioned previously, I think it would be good to have in multiple locations… Just like on a motorized conveyor - usually an e-stop every X feet or at point of access.
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