Homing issue with RDC6445S (EC) controller

I have a home built laser based on the Further Fabrication design that I’m trying to get up and running.

I can’t get the homing/reset function of the Ruida controller to complete successfully on the controller or the Lightburn software. The machine is built with NC manual homing switches in the top left position. X is 1200mm left to right and Y is 750mm top to bottom.
No combination of motor wiring along with Direction polarity or Key direction will home the machine with 0,0 at top left. 0,0 is always at bottom right, so if I manually trip the home switches at the bottom right position then I can jog the machine but positive motion is left and up. If I let it home at the top left you can’t jog off the switches because jogging right is negative. No combination will allow a home left with Key direction correct and the position readout going 0 to positive with movement to the right.
If I use Lightburn it homes towards the correct direction but just crashes into the stops as it doesn’t see the switches. I have searched for the solution and have seen similar issues on the web but no clear solution as to the configuration that will fix this.
I’m wired into Lmt X- and Y- and the controller is responding to the switches being activated. Since I went with NC on the switches LED one and three are illuminated until activated by the X or Y axis.
I have selected upper left in the software where indicated for home position. I can jog the machine with the control panel and in the software but can’t get past this basic homing step. Very frustrating.
There has to be some fundamental setting I’m missing. Any help is appreciated.

NC home switches are usually wired to ground, so it’s grounded when it is not active and the controller will pull it high when activated.

You need to tell the Ruida that the input is inverted. The Ruida controls are mostly ‘wired or’, they need to be pulled to ground… A NO switch.

Did you change the controller for an inverted home switch?

You can also look on the diagnostic screen ‘Z/U → Diagnostics’ of the Ruida console and the status of the inputs are displayed.


Check out this thread… kind of long but same issue…

Take it one step at a time. Many of these setting will impact multiple areas. Get it to home, then worry about anything else.

:smile_cat:

The home switch polarity was the key. Since I’m wired NC into the Lmt X- and Y- and the GND inputs on plug CN4 “Lmt polarity” needs to be positive. It’s weird that the controller still responded when set to negative.
I’m curious what the correct sequence of motor wiring to menu selections should be.

Example: Wire motors so that Dir polarity negative is left or up and Dir polarity positive is right or down.
Key direction set for correct direction when using control panel.
And last but probably first setting is Lmt polarity negative for NO switches and positive for NC switches.
My machine settings are X axis Direction negative, Key direction positive and Lmt polarity positive. Y axis is Direction negative, Key direction negative and Lmt polarity positive.
It now homes with the controller and in LightBurn.

Thank you for the help.
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Great, so I guess it’s working?

The other adjustments you’ll have to play with…

The main issue is to start at the beginning and work your way though until it’s operating properly…

Glad it’s up…

:smile_cat:

It’s more difficult for those of us wiring things “in the field” from assorted retail parts than for a manufacturer with known sources, because we have no control over color codes / connectors / orientation. AFAICT, the least awful way is to wire (retail) things consistently, then fix it in the mix.

So you set Limiter Polarity to match whatever switch you just installed: True for NC switches, False for NO switches. When it’s set correctly, the input signal will be active only when the switch is pushed.

Then you pick Direction Polarity so the axis moves toward the switch during the homing operation when the controller resets. There seems to be no other configuration for the stepper driver DIR signal. Given the random colors and orientations of stepper motor wiring, there’s no way to tell which way it will rotate before connecting it and trying it out.

Finally, pick Invert keypad direction so the axis moves the way the control panel buttons suggest. This also controls how LightBurn moves the axis: both should go the same way.

Repeat for all axes and it’s all good. Maybe …

Yes it is working great. Right now I’m playing with trying to get a diode laser module to work on the laser 2 spot in the controller. Running into the same issues as other threads that it turns on and off but won’t vary power or pulse in between engraving items. But it is firing and the machine has been calibrated and homes properly now.

Thank you for posting this as it fixed the same problem I had with the RDC-6445S. Thou I had to reverse the Stepper Motors to get the right direction to work and went into the Controler to make the adjustments. But all is good now.

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