DWC 3.5.0-rc.1 disconnects after a while
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Hello
I have recently upgraded to the RC version of DWC and reprap firmware on my duet 2 ethernet. I installed the G-code viewer plugin to check if my printer is still doing the right thing. After a while the DWC disconnects and I couldn't reconnect unless i dis- and reconnected the ethernet cable. So I figured I would stop using that plugin to avoid issues. However now the printer also disconnects when just looking at the job status page.
I get (a lot) of high temperature warnings for 2 of my drivers (looking into adding a cooling fan to cool the heatsinks), so that might be the cause?
Or is there something else that might be wrong?
Thanks in advance! -
Are the drivers actually hot to the touch when you get those warnings?
What kind of cooling are you using now, how is it mounted?
What motor current are the drivers using? -
Hello thanks for your reply!
Yes the heatsinks on the drivers are fairly hot to the touch. Currently i have them mounted directly on each driver with thermal paste.
X motor is set to 1700mA
Y is 3400mA (dual Y motors)
Z is 2500mA
Dual extruders are set to 500mA eachWhen starting a print just now, the interface disconnected again (bed was still warming up). So I'm thinking either my ethernet chip is failing or the RC has some hickups on my board
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Those motor currents are pretty high and active cooling would be recommended.
Heat sinks are usually quite ineffective because the drivers are actually synced to the copper ground plane of the board itself. A heatsink on the plastic cap doesn't help much. The best way to ensure proper cooling is to mount the board so that it is upright to allow for an upward convective draft, and if more cooling is needed, add a fan for forced convection, particularly on the back side of the board.
Are you able to test 3.4.6 to see if your connection issue is resolved there?
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@Stan I'm pretty sure you can't set currents higher than 2400ma on a duet 2 so that 3400 won't be 3400
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Thanks for all your feedback! I have now raised the board up and installed some fans (in addition to the heatsinks, because they were getting fairly hot so they must be doing some cooling). I have been printing a lot and have not had the overtemperature or disconnect issues. Never would have guessed that the webcontrol would be affected by hot drivers... Lesson learned!
As for the motor currents: I have no idea wether or not my drivers reach the presets, but at this point it works good enough to leave it alone
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@Stan said in DWC 3.5.0-rc.1 disconnects after a while:
Y is 3400mA (dual Y motors)
If you're using a Duet 2, the motor current is probably just set to max, ie 2.5A.
Are your motors wired in parallel? I'd guess they are if you have doubled the motor current. However, due to the current limit of the Duet 2 drivers, they are only getting 1.25A each. If they are wired in series, the voltage is doubled rather than the current, which the stepper driver can do itself. You would potentially lose top speed, but the controller would run a lot cooler.
Ian
