Using Panel Due 5v for fan
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(Duet 2 Ethernet) I would like to put a small 5v 30mm fan in my Duet case blowing in under the stepper drivers. It is mounted horizontally and will have a 40mm 24v fan blowing down on the top of the board using the normal fan connections as all the printer fans are 24v. I read the fan doc and searched some here but did not find a simple way to do this, I have buck regulators but don't want to bother adding more components I don't really have room for. Looking at the board diagram there is a 5v and ground for the Panel Due which I am not installing, can this be used to power an always on cooling fan? If so, I assume I have to do some config work to turn on that power output as if there was a Panel Due, and let me guess, if no Panel Due is detected the board will though an error??
RepRapFirmware 3.x and later: Using a PanelDue with Duet 3 and Duet 2 and RRF3 will require M575 P1 S1 B57600 being present in config.g.
Is that M575 needed to turn on the 5v or just enable the io ports? Guess I can power the board with USB and see if I have 5v at that pin... And Yes, yes there is 5v without an entry in config.g! So any reason I can not use this aways on 5v pin to run a fan??
If I can't grab 5v someplace I guess I will do without this fan, not sure it is really needed as those 5v pi fans don't move much air at all. -
@airscapes said in Using Panel Due 5v for fan:
If so, I assume I have to do some config work to turn on that power output as if there was a Panel Due, and let me guess, if no Panel Due is detected the board will though an error??
No, I believe the 5v will be present regardless. You can check with your multimeter.
If you already have a fan in your case you may be fine. What stepper current will you be using? How confined and enclosed is the Duet in the case? Having some air flow across the front and back of the board is ideal, but if you are using stepper current below the 2.4 max you likely won't any any issues with your single fan.
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@phaedrux said in Using Panel Due 5v for fan:
You can check with your multimeter.
What stepper current will you be using? How confined and enclosed is the Duet in the case? Having some air flow across the front and back of the board is ideal, but if you are using stepper current below the 2.4 max you likely won't any any issues with your single fan.
Yes the 5v is there with no config so I assume it is safe for a tiny fan.
Not sure on the current, I think the stepper motors are Nema 17 but I can not find any specs as yet on them as related to the Makergear M2.
I did read someplace the amperage is set by the marlin firmware and it is in some config file. Since I now know more about RepRap then I ever learned about marlin, I have no idea where to look yet. UPDATE found the firmware for the M2 and looked through the Configuration_adv.h and found this info.. but not sure what it means exactly but guessing they are set to .75A and Josh change the extuder to 85 which seem to be just slightly higher than .5Amps, if I am guessing correctly:-)// Motor Current setting (Only functional when motor driver current ref pins are connected to a digital trimpot on supported boards)
#define DIGIPOT_MOTOR_CURRENT {135,135,135,135,135} // Values 0-255 (RAMBO 135 = ~0.75A, 185 = ~1A) //changed E0 motor current to 85, from 135 - 1/12/2016 JoshThe Duet enclosure is only slightly larger than the board to fit in the same space as the stock Rambo and attach with the same screws etc. I am probably over killing the cooling but better safe than sorry, not like it is expensive or difficult to add it at this point. So the main 40mm 24v fan will goin in the top and bow in and the the 30mm will go in the front and blow in. It is almost halfway below the the board.
So I guess my next step tomorrow is to take some pictures of the rambo and start wiring the Duet.
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For current on the Duet the rule of thumb is to use 60-85% of the max rated current of the motor.
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@phaedrux said in Using Panel Due 5v for fan:
For current on the Duet the rule of thumb is to use 60-85% of the max rated current of the motor.
Ok, will need to contact MG support as the replacement motors they sell on their site do not list it, nor is it on the wiki.. Don't see any stickers on the motors.
I would assume I am safe using the values in the current marlin for the machine? -
yeah the marlin values are likely lower I think so that would be a safe starting point.
