Follow up questions for Ruida 644xs config

Below is original text with follow up questions:

The weather has finally warmed enough to work on the machine. My original issue with the issue with Ruida 644xs is the laser tries to seek the bottom left corner when it should try for the top right hand corner. This is where the stop sensors are located.

I updated to latest LightBurn and the software auto recognizes my machine. It is still searching for bottom left hand corner.

Previous notes said to try and reverse the polarity via Machine Settings. I reversed polarity for X and Y, under Limiter Polarity, but when I hit OK, and try to send laser home (top, right) the change from False to True does not save and it still tries to find bottom left.

Any news or updates on this issue? The latest version of LightBurn recognized my system and Ruida card, but it still points to the bottom left. Any assistance on this would be greatly appreciated.

Please let me know if I let out any pertinent information.

Thank you.


Original text below:

Oz via LightBurn Software Forum <>

Sun 2/3/2019 1:47 PM
February 3

This sounds like your motors are running reversed, or the vendor settings are incorrect - the machine should be seeking the corner with the limit switches at the rear right when it starts up, and since it’s not finding them it’s defaulting to 10000, 10000.

There’s a setting in the X and Y axis config in the Machine Settings, I believe called “Limiter Polarity” that controls the homing direction. Write down anything you change so you can reset it if necessary, but I would try changing those.

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Thank you OZ. I replaced the cable and the talking is better. One thing I noticed - I think I have narrowed the issue down. I replaced the USB cable and that seems to have helped. In doing so, I think I spotted what the issue may be - on the Ruida display, it is showing the X and Y axis as both be…

The direction that the controller moves when it starts up is a setting in the controller, nothing to do with the software, aside from the software letting you change those settings.

The “Direction Polarity” setting controls which way the motors move in general. Normally you would connect the LmtX- and LmtY- terminals to your limit switches, as these are the “Origin” wires and the others, LmtX+ and LmtY+ are the maximum travel end-stops.

I think I misspoke earlier - The Limiter Polarity could be choosing whether the limit switches are normally open or normally closed. This is hardware specific, and normally set up by the vendor who sells you the machine with the controller, so I don’t know all of this by heart yet.

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Thanks for following up. I’m not sure if I have a hardware or software problem at this point. I installed the Ruida according to the way the old card was set up. I’ve never had it up and running. It continues to point down and left no matter what settings I use.

Using the Limiter Polarity doesn’t solve anything on this end. Once clicked and saved, I have reopened the Machine Settings and find they are unchecked again. I ordered the Red and Black Machine from China, so I don’t have a vendor to reach out to for help. Thanks for following up, I’ll do some more research.

After you change the settings, you click “Write” to write the settings back to the controller?
First Read, then change settings, then Write.

Limit polarity has to with what signal the controller expects from the limit switches. Direction polarity is what you need to change to alter the direction the motor moves when homing.

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