Turning on electric sander freezes print

[Baldovin]

Hello,
My Rostock Max V2 stops mid print when I turn on a bench sander in my shop. The sander is somehow causing the Rostock to break connection with the Tablet. To correct I have to turn everything off, reboot, and restart the software from the beginning of the print. The printer is running with a Matter Control Touch tablet.

I have rewired the circuit in my shop that the Rostock is plugged into to. The Rostock circuit is a dedicated ground circuit with a GFCI. The Sander is plugged into a separate circuit with its own hot and neutral and is GFCI. All of the boxes and conduit share a common ground.
Has anyone seen this before? Please help.

[BenTheRighteous]

Does it happen if you're printing off SD?

How long is the cable connecting the tablet to the printer? Maybe try a shorter cable.

[Baldovin]

I have not tried printing off of the SD card. I will try that next. I am also going to try printing off of a laptop. It would rule out the tablet then. The cable is the stock one that shipped with the printer, 4'9" is what sticks out so it is a 5' cable.

[geneb]

You might also try putting a ferrite core on the USB cable. That sander is going to throw out a ton of noise and the USB cable may be picking it up. You might want to check for any loose connections in the sander as they may be excascerbating(sp) the noise generated by the motor.

g.

[Eric]

I assume your bench sander has a large motor. Motors can draw 6+ times their normal current during startup. A separate circuit is a great start, but it still all comes together in the fuse panel. I bet you're affecting the power quality for the entire house during motor start. GFCI is only a safety device; it's not a surge protector and doesn't stop load/power quality issues. Here's a white paper that may help you: http://www.apcmedia.com/salestools/VAVR ... irect=true. Skip to the table on page 17 if you dont want to read it all...and the power supply discussion on page 20.

You could try a surge suppressor for the Rostock equipment. The cheapest version of that is often found in power strips....I'd recommend that as a minimum for all electronics, regardless of your power situation.

The solution I'd suggest is a UPS for the Rostock setup. It'll kick in when the power quality goes out of spec...and kick out again seconds later when the motor has started. Plus it'll give you protection against actual power failures that don't last too long.

You can also get soft-start devices for large motors, but that would probably cost more than a UPS.

[BenTheRighteous]

These are all good suggestions. Finding out whether your printer gets interrupted when printing from SD will tell you which ones you should follow up on first.

[radicaldev]

I had the same problem. Moved my printer onto the ups I use for my workstation and it went away.

[Baldovin]

OK,

Sorry for the delay. I have been having an unrelated computer problem that was finally solved last night. Today I was able to print using my laptop computer connected by the stock USB cable that shipped with my Rostock. My client is Matter Control. The print started and when I started the sander the print was not interrupted. So if I am understanding your suggestions, the USB cable is good, the Rostock is good. So this leaves me to suspect the Matter Control Touch or the USB adapter that is between the matter control touch and the Stock USB cable.

What are your thoughts?

Thanks

[BenTheRighteous]

I assume the MCT is plugged into power all the time? Does it have a battery? Try doing the same thing with the MCT running on battery.

Maybe if you're a wiring whiz, you can power the MCT off the power supply in the printer, if the problem winds up being that the MCT came with a crappy power adapter.

[Mac The Knife]

Matter control touch does not have a battery.

[BenTheRighteous]

Oops. Well my suggestion stands, which is to replace the power adapter. It would be a cool hack to get the tablet to run off the same supply as the printer.

[Baldovin]

OK, I ran down to JK Electronics to buy a 1.1mm plug and wired it up to my bench top power supply and powered up the MCT and Rostock, then started the print. Turning the sander on and off did not stop the print. So it looks like the MCT power supply does not have sufficient line filtering to handle the sanders power up and down cycle.

BenTheRighteous^^ I had the same thought, after I complete that test I will post up again. I am hopeful that the Rostock will power everything up without issue.

Thank you everyone for helping me to think this through!

[Baldovin]

Using an extra 5V pair from the Rostock PS worked perfectly. I put it all together and tested it: pass. This is an elegant solution, I like it!

Thank you again for helping me out. I will post some pics on my facebook page "Seal Beach Maker Space" to document the mod.

[BenTheRighteous]

Awesome, glad you got it worked out!