NPN PROXIMITY SENSOR FOR DUAL STEPPER MOTORS ON Y-AXIS
Hello Gents
I am in the process of completing my CNC router build. It is a "Maker slide" design and has two stepper motors on the Y-AXIS. The BOB is an AKZ250 3-AXIS version.
A search on YouTube, showed how to connect two of these NPN proximity sensors in PARALLEL and how to add a resistor, to lower the voltage to around 5 Volts, for the BOB.
As I am new to this CNC router build, I have a question, regarding the use of the NPN proximity sensors, for two stepper motors on the Y-AXIS rails.
My question is if 4 proximity sensors, can be connected in PARALLEL? Meaning one sensor on each corner of the Y-AXIS rails?
A thought crossed my mind, by having two sensors on the Y-AXIS (One on opposite corners to each other). So if the gantry moves towards me, the one sensor will be activated at its end of travel and when it moves away from me, the other sensor will be activated, at its end of travel. The stepper motors on the Y-AXIS have their own driver.
I assume if 4 sensors are connected in parallel, it should be able to work?
Re: NPN PROXIMITY SENSOR FOR DUAL STEPPER MOTORS ON Y-AXIS
Looks like that BOB has pulled-down inputs, so you'd need to connect the emitter to gnd, have a 330 ohm resistor going from +5 to the input, and also have the collector of the sensors connected to the input.
Shouldn't be any problem having all of them in parallel as long as they're normally open switches.
Not sure how useful this will be though. Proximity switches are good as home switches, but simple limit switches are generally better for overtravel switches. In the case of overtravel switches, the best to use is normally closed limit switches, in series. That way if a wire breaks it will throw an error, rather than letting your router crash.
NPN PROXIMITY SENSOR FOR DUAL STEPPER MOTORS ON Y-AXIS
Reply with Quote
