Ok. I’m drawing a blank. I have made the decision to change to optical endstops with the same 3 wire configuration, vcc(+5 CSC), GND, signal. The switch is a normal closed, so signal is there when the switch is open, and drops to 0 when the switch is closed. I want to run 2 switches on each axis, and I’m drawing a blank on how to connect the wiring. I am running an optoissolator for the switch already, and one switch works great. Diagram for that is attached. now my Problem is when I attach 2 switches per axis I can’t figure out the wiring to make it work. I have tried a few different things. And none have worked. I took the signal from switch 1 to the 5v vcc in on the 2nd, and the signal from the 2nd to the optical, which I though would work, but nope. any ideas would be appreciated. I will probable run one switch for now, and add the additional later, just to get the new controller pack installed. thanks in advance!
May need to throw in an OR gate (made of diodes or logic chips) so that when either goes low, it pulls down the signal pin
Honestly, it would be easier to configure them normally open. With your config, al long as you have a signal the system won’t consider the limit switch triggered. To do that both switches works have to trigger to get the signal to drop. Or setup additional electronics like Peter noted.
I think this would be an AND gate for this inverted use case? If either goes low, the output goes low. I guess XOR would work too, it just needs a way of differentiating between both inputs high and one or the other input high. Either way, this was gonna be my solution on the laser for my optical stops. A 74HC08 quad AND IC is dirt cheap to solve the problem, doesn't need a bunch of supporting components. I decided in the interests of expediency, mechanical normally-open switches were the way to go instead. Of course, then I lost a lot of time chasing noise issues, so the chip would probably have been the better option. On the other hand, I no longer have any interest in 5V machine signalling, and mechanical switches take 24V a lot better than silicon (usually) does!
I will say that the normally open mechanical setup for the Lead 1010 I have.. are very very finicky and sensitive... I don't have a dust shoe.. so sometimes I just stand there with a using my shop vac sucking up the dust.. and if I come within 5 inches of the frame of the switch the static charge from the dust in the plastic hose triggers the limit switches. Also.. if I am running a job and I plug my macbook power (usb c) it also triggers the limit switch.. even though my macbook is 6 feet away with a long USB cable... I did find a config for the BlackBox with a NC configuration, which I am guessing is the same for the XPro V4 I have, I will eventually set it up that way.
Sounds like you have the wrong dust hose. IE the type that can cause explosions due to static buildup (; You want an antistatic one, or at least throw a length of bare copper wire down the inside, earthed on Vacuum side! Apart from EMI it really is a fire risk What are Anti-Static Hoses? | Static Dissipative/Conductive Hoses For the Mac, try increasing debounce gnea/grbl
Thanks! Looks like the AND gate will be the way to go. I will add this logic to the board that i have built. At the same time, since I am adding this, I will add the logic for the Flow meter for the spindle cooler and water level detection. This breakout is getting fun.. All those electronics classes I slept through would be good now..
the explosion aspect is way over blown. Myth busters did something on it, as well as Stumpy Nubs (his video here is a good watch) it’s more an annoyance, but I have become very adept at clearing out the already run gcode and picking up where it left off after the alarm trigger. Should put something like that into the control software.
