I (and johnbernard36) have spent 3 days or so on and off trying to get a relay board working with the Planet-CNC USB board. It works fine on Mach 3 driving a standard printer port via the computer. The relay board being used is the Mechtronics relay board which you may have used on earlier Phlatprinters.

Now mind you, we are using a DIY USB board, not the one that ships with the Phlatprinter , but I suspect it may well have the same issues, so this post is to identify the problem I am seeing and find out if anyone else has any similar problems if and when they build their units.

Also, to add to the confusion, I am using a Gecko G540 controller instead of the Mechtronics board that ships with the Phlatprinter .

With the above in mind, here is what I have found...

There are two separate issues we are dealing with.

#1 When the spindle relay activates and applies power to the spindle, 90% of the time, the USB board locks up.

#2 Of the two relays we are using, one for spindle and one for vacuum, only one works. Pin 1 of the DB25 will drive the relay, but pin 17 will not. Again, this is using a Gecko controller, but Mach 3 works for both relays.

After much head banging, we have come to find out that the spindle motors brushes are generating enough electrical noise as to trigger the lockup condition. Doing nothing more than issuing a M3 command will lock up the USB board requiring a hardware reset or closing the program and restarting it.

Now I have been able to provide a work around, but I would be interested in hearing suggestions for a better solution.

I had a UPS battery backup in the shop for my computer. I plugged the battery backup into the switched outlet in which I normally have my spindle motor plugged into. I plugged the spindle motor into one of the surge protected outlets of the battery backup. In this configuration, I can start the spindle using the USB controller and it does not lock up.

During the course of our troubleshooting, we took my board over to Johns shop and fired up another type of brushless motor in close proximity to the USB controller while it was running gcode. We were able to lock up the USB controller there as well.

So, my concern is that over time, as the brushes wear on the spindle motors, will they generate more electrical noise and if so, will it start affecting the USB boards? Is the problem only with our custom USB DIY board, or is it a common problem with any of the USB boards? Time will tell. It is too early to make any assumptions, but it is something we need to keep a watch out for.

If you encounter any of these lockups please let me know. The escape key on the keyboard will not interrupt the software once it locks up. The only way to clear it is shut down the planet-cnc software or do a hard reset of the board.

I would like to hear from anyone who attempts to hook up a relay board to the standard USB board and Mechtronics controller.

 

Update...

I resolved the noise problem with the purchase of a Belkin Surge Protector Model BZ108201 - 08 which I got from Home Depot. The specs list EMI/RFI Noise Filtration from 150khz to 100MHz to 43 dB Reduction.

I am now able to turn on both the vacuum and spindle without affecting the USB board.

The computer and all other receptacles are running off a UPS battery backup.

 

Clip a Ferrite magnet around the wire

http://www.mpja.com/prodinfo.asp?number=18466+FL

 

I just started using my PP3 and am having the same problem with spindle noise. Have you actually used the ferrite magnet trick, or is it merely a suggestion? I have seen this employed on aircraft avionics.

 

I use one with zero problems, it is a cheap thing to try, your results may not be as good as mine

 

I tried the Belkin surge suppressor, but still no luck.

 

Did you connect only spindle to Belkin surge protector? Or something else?

 

The spindle and the power supply. I'll try just the spindle. Thanx

 

Plug the spindle into the surge protector. Plug the surge protector into the relay board or directly into a switched AC power source.

Better yet, install a router or rotozip and you won't need the surge protector.

 

Thanks for the input. It seems to be working now.

I may do that---I'm not real impressed with the spindle, but I'll try it for a while first.