RDC6445G how to control 220V Z axis motor?

I recently purchased a 150W laser, equipped with a Ruida RDC6445G,
I also bought a Z axis probe yesterday which I installed and connected to the Ruida, so far no problems.
Where I struggle is connecting the Z axis motor to the Ruida.
Indeed, the controller is equipped with a +5V/PUL/DIR socket… but the Z axis motor on my laser is a 220V reversible YN60 motor.
The motor is directly wired to the up and down buttons on the side of the machine.
Is there a way with a relay or controller to be able to control it directly with the Ruida to allow auto leveling? (and incidentally keep the possibility of continuing to use the up and down buttons in case of forcing, but this is not necessary if I can use Z-Z+ on the screen)

Here is the schematic of the engine and a reminder of the ruida.

I found lots of relays on Amazon to control a motor like that with an arduino, but it doesn’t seem at all compatible with the PUL/DIR

Ideally I would like not to replace the 220 motor of the Z to avoid having to buy a Nema

I thank you in advance

I’ll preface this by saying that there’s a lot of personal opinion here. Others may value things differently.

Any particular reason why? I suspect at the end of all this and with what you want to do with it that replacing the motor and adding a driver will be the most expedient and result in the best experience based on what you’ve stated as goals.

Even if you went with the current route your basic challenge is converting the existing AC motor into a closed loop AC servo motor. You’d need to add a servo driver and servo motor encoder to drive and track motion.

In the end if you want a controller driven motor solution allowing you to do auto-focus type functionality in my opinion it would simply be easier and likely cheaper to replace the motor.

Alternatively, if you weren’t insistent on controller functionality you could wire up an electrical solution with a limit switch set to a specific location that shuts off the motor when that switch is reached to achieve a primitive Z homing.

Basically, no.

The controller expects to deal with a motor having controllable speed and direction, so that it can precisely position the platform relative to the home / focus sensor.

The AC motor is intended for manual switches, without speed control.

Unfortunately, you must replace the AC motor with a (large) stepper motor and add a suitable stepper motor driver.

Of replacing it or it actually being worthwhile to have that available?

@berainlb and @ednisley correctly gave you the bad news…

Good luck


I meant in terms of my evaluation about relative value of attempting to do the mod vs just buying the easiest solution to the problem.

Because sometimes the easy way are the most expensive (80€ a driver and a big nema23)
And also because sometimes it’s cool to do something what other never did and evolve, you know ?

There is absolutely nothing wrong with doing things the hard way, just for the learning involved, and I highly recommend it.

However, I assumed someone who just bought a commercial high power laser was more interested in using it than tinkering with it.

When you ask for advice about doing something from a group with considerable domain knowledge and everybody tells you it’s a bad idea, you don’t have to take their advice, but …

If you do go the stepper route, you should use a NEMA 34 motor to get enough torque at a reasonable speed. That’s what OMTech put in the bottom of my laser and they’re not noted for spending money unnecessarily.

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