Should I stop using this board?

Mentaluproar

My duetwifi has been moved between multiple printers. I love it so much, every time I get a new machine, the first thing I swap in is my duet board. I have had to repair it a few times. The connectors for the bed and extruder heaters broke free (tiny gaps between solder and the pins) and had to be resoldered. It's been a great board.

It was just installed into my ender 6. While working on tuning, I noticed the bed heats MUCH slower than the stock board. It was slow then too, but it wasn't as severe as now. It shouldn't take 5 minutes to hit 70C, should it?

I also notice the fans spin much more slowly than if I directly connected them to the PSU. A little slower is expected, but this is quite a bit more than normal.

My theory is that along the way, something must have broken or worn down that I haven't seen yet. It's been several years, so maybe I should just retire this board. Ideas?

o_lampe

@mentaluproar
Slow heating indicates, there is a severe voltage drop somewhere in the path. Could be the connectors Vin and Bed or the MOSFet dying.
Anyway, it can cause molten connectors and fire.
You can use a voltmeter to measure voltage drop and probably find and fix it.

The fans run on Vin, too? Some users had issues with fans spinning slower (50%ish), because they had a wrong setting in config.g.
#MeToo
I confused heatsink fan and part cooling fan definitions for the tools.

dc42

@mentaluproar the first thing to check is that the VIN and bed heater screw terminals on the Duet are tight and show no signs of burning, and the solder joints to those terminals on the underside of the board look in good condition.

Next, if you have a multimeter, use it to measure the PSU output voltage, the voltage across the screws of the Duet VIN terminal block, and the voltage across the screws of the bed heater terminal block while the bed is heating at full power and is still a long way from reaching the target temperature.

Mentaluproar

@dc42 I disconnected the bed in the chamber and measured there. 24V dead on. o_lampe, what s this about adjusting fans?

jens55

@mentaluproar said in Should I stop using this board?:

@dc42 I disconnected the bed in the chamber and measured there. 24V dead on. o_lampe, what s this about adjusting fans?

That doesn't really tell you anything. Measure with everything connected like when you are experiencing troubles.

Mentaluproar

@jens55 So measure in parallel with the bed rather than measuring with the meter connected where the bed would normally be?

EDIT: 23.4v. not great, but not bad either, right?

jay_s_uk

@mentaluproar the PSU could be on its way out

Mentaluproar

@jay_s_uk It's a brand new printer.

jens55

@mentaluproar said in Should I stop using this board?:

@jens55 So measure in parallel with the bed rather than measuring with the meter connected where the bed would normally be?

EDIT: 23.4v. not great, but not bad either, right?

That is perfectly acceptable.
Just to clarify in my mind .... if you replace the Duet with the original controller without changing ANYTHING else on the printer, your original controller heats the bed up measurably faster ? .... and you measured 23.4 volts at the bed terminals during heat-up when the bed was cold so the heater would be on solid ?
If you confirm the above, the only thing left that could slow heating would be if you specified a less than 100% duty cycle in your config.g file for the printer and at the same time you used a poor quality meter that would only show peak voltage.
5 minutes to hit 70C is relative. It could be perfectly acceptable as long as both controllers take the same time.

Mentaluproar

@jens55 I rolled back to the stock board and will just be using Klipper for it instead while I take a closer look at this board. I cant turn the parts fan on and off so I think there's a dead mosfet on here too. I measured with the stock board and it was 0.2 volts higher than the duet. I tuned the voltage up just a touch to hit 24 even even with the bed head on. shouldn't matter but meh.

My soldering skills are potato-class so I might not be able to repair this board.