1 Topic by ebarton97

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Topic: Drivers too hot

Hey guys. Been having a lot of problems with my printer lately. I thought I had them all fixed but things are actually getting worse. I'm using a Prusa i3, ramps 1.4 and drv8825's on all my drivers.

During a print my x motor shut off and the y motor continued. I attested this failure to a thermal shutdown on the drivers. They got extremely hot and so did my motors.

So naturally, i turned the vrefs down today. I didn't use the measurement way but i turned them down until the motors wouldn't run then turned them up a little bit. Now the drivers and motors are getting hotter quicker so much that i cant run the x motor more than 50mm without a shutdown(i'm still thinking thermal shutdown because once it rests for a minute i can repeat the process).

I have no clue what to do. And yes, to turn down the vref i turned the pot counterclockwise. I don't have a fan blowing directly on the drivers. Any clues as to keep everything from shutting down and why, even at minimum vref, everything is too hot? I barely ran my printer for ten minutes when it shut down. I'm desperate for answers

2 Reply by wardjr

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Re: Drivers too hot

They will get too hot with too low of current just as too high.  Turn them up slightly and no matter what get a fan blowing on them.  Don't forget that drivers fail and excess heat will decrease their lives.

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3 Reply by carl_m1968

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Re: Drivers too hot

My guess is you fried the DRV88 even though that is near impossible for those chips as they can handle 2+ amps if heat sinked. But I would first buy new drivers. You could also have bad motors now as well. When things get too hat bad things happen.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

4 Reply by ebarton97

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Re: Drivers too hot

wardjr wrote:

They will get too hot with too low of current just as too high.

I didn't know that! I guess I'll get the multi-meter out and actually set it correctly. We'll see if that helps. As soon as i get printing again I'll make some fan mounts.

Does anyone bother cooling their motors too?

5 Reply by ebarton97

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Re: Drivers too hot

carl_m1968 wrote:

My guess is you fried the DRV88 even though that is near impossible for those chips as they can handle 2+ amps if heat sinked. But I would first buy new drivers. You could also have bad motors now as well. When things get too hat bad things happen.

Neither the drivers or motors are fried. I can switch all the boards around and they all function fine. I can also plug different motors into different drivers and they all run. So it's not a problem there. The DRV8825's have only an hour or so of run time(which i know doesn't excuse them from being fried, just saying).

6 Reply by ebarton97

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Re: Drivers too hot

***UPDATE:

Somebody please tell me that its not an easy thing to know or i might cry. I turned the pots CLOCKWISE this time. It seems thats the direction to lower the value. Why didn't I know this? Thanks all for the replies.

7 Reply by carl_m1968

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Re: Drivers too hot

Normally clockwise does not increase. I use DRV88's as well and I can assure that counter is lower. What might have happened is that they where at max. These pots do not have a stop so you can turn them past max and back to minimum by turning the same direction too far.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

8 Reply by wardjr

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Re: Drivers too hot

carl_m1968 wrote:

Normally clockwise does not increase. I use DRV88's as well and I can assure that counter is lower. What might have happened is that they where at max. These pots do not have a stop so you can turn them past max and back to minimum by turning the same direction too far.

In a nutshell ^that

Printit Industries Model 8.10 fully enclosed CoreXY, Chamber heat
3-SD3's & a Workbench all fully enclosed, RH-Slic3r Win7pro, E3D V6, Volcano & Cyclops Hot End
SSR/500W AC Heated Glass Bed, Linear bearings on SS rods. Direct Drive Y-axis, BulldogXL
Thanks to all for your contributions

wardjr's Website