SB2040 part cooling fan

[RainerBoden]

I finally got around to do the CAN upgrade.

While checking everything so far, I noticed my part cooling fan is slower on lower percantage than usual. Normally 10-20% the fan moved allready pretty fast. But now I can basically follow the individual fan blades while the fan is rotating. Hard to tell, but I would say its more than 50% slower than before. But 100% seems to be the same (moves lots of air and actually sounds as loud as I remember).

 

I went from the LDO toolhead board (with the 15 wire cable or however many wires there where) to the SB2040V2 CAN board. The fan is a 2 wire fan connected to the HartK fan pcb from the LDO toolhead board (as its the same as the SB2040 one).

My old Cfg was:

[fan]
pin: PA8
kick_start_time: 0.5
off_below: 0.10

Now I have:

[fan]
pin: SB2040v2:FAN0
kick_start_time: 0.25
##cycle_time: 0.15
off_below: 0.10

(FAN0 is gpio13)

I played around with different cycle times and kick start times, but enabling any cycle time made it just worse and kick time didnt solve the problem.

Maybe someone had the same problem while upgrading? Or at least knows what I can check/have to change to make the fan run better again.

[Nurgelrot]

Not running a 24v at 12v are you?

[RainerBoden]

The fan is 24V, but the SB2040 should output 24V for the fans (at least according to the documentation).
I am directly running 24V to the toolhead from the PSU, so 24V are definetly at the toolhead.
But I will double check that the fan header actually outputs 24V.

[RainerBoden]

The board spits out 0-24V at the fan pin. Cant measure the PWM as I dont have a scope. But I can see the voltage fluctuate, so it is definelty using PWM (ofc, 0% = 0V static and 100% = 24V static)

[mvdveer]

5 hours ago, RainerBoden said:

The fan is 24V, but the SB2040 should output 24V for the fans (at least according to the documentation).
I am directly running 24V to the toolhead from the PSU, so 24V are definetly at the toolhead.
But I will double check that the fan header actually outputs 24V.

I am running Mellow boards and the fan power output is controlled by the breakout board in the toolhead. I suspect the hart toolhead breakout is different to that of Mellow. (I Don't have one to compare) 

See the Mellow documentation here for the SB2040 v 2 toolhead and breakout board.

Mellow Fly 2040 v2:

  

DOn't know if this will help, but all I can think of.

 

 

[ChicagoKeri]

Am using a SB2040v2 as well.   I seem to have similar results to you.

Some observations of the parts cooling fan, with the 2-wire 5015 fan wired to AGND and 24v:

100% - fan runs at full speed.  50% - fan runs fairly slowly. 20% - fan runs slowly.  10% - fan runs very slowly, able to watch blades move.  7% - fan runs extremely slowly, on threshold of stalling.  4% - fan stalls.

As I usually print ABS, PC or sometimes PPS, I seldom use the parts fan and haven't noticed the relatively low speeds until you mentioned them.

 

 

[kharrisma]

Can I ask exactly which fan you're using?  Is it a four-wire fan and you're using only the two power leads, or 'natively' just two-wire?  I had a similar issue, but I'm using a Honey Badger 5015, four wires, not using the PWM, just power and tach.  The fix proved to be changing the cycle time to match the PWM frequency of the motor (even though I'm not using the PWM lead... actual setting ended up working best at "cycle_time: 0.00007" (which works out to something like 17 or 18 kHz, where the stated  PWM freq for the motor was 25 kHz (setting for that would be 0.00001.   It's not perfect,  but it's a ton better than no spin at anything less than 49%, roughly 20% of full speed at up to 99%, and runs like a leaf-blower at 100%.  With that setting, now I get a steady increase of speed from zero up to 100.  Likely not what's happening in your case, but my issue was similar to what you describe, and that's what fixed it (Nitehawk-sb toolhead, USB interface.)

[ChicagoKeri]

26 minutes ago, kharrisma said:

Can I ask exactly which fan you're using?  Is it a four-wire fan and you're using only the two power leads, or 'natively' just two-wire?  I had a similar issue, but I'm using a Honey Badger 5015, four wires, not using the PWM, just power and tach.  The fix proved to be changing the cycle time to match the PWM frequency of the motor (even though I'm not using the PWM lead... actual setting ended up working best at "cycle_time: 0.00007" (which works out to something like 17 or 18 kHz, where the stated  PWM freq for the motor was 25 kHz (setting for that would be 0.00001.   It's not perfect,  but it's a ton better than no spin at anything less than 49%, roughly 20% of full speed at up to 99%, and runs like a leaf-blower at 100%.  With that setting, now I get a steady increase of speed from zero up to 100.  Likely not what's happening in your case, but my issue was similar to what you describe, and that's what fixed it (Nitehawk-sb toolhead, USB interface.)

Just a 2-wire 24v 5015 blower wired as such. For my use case, it's not an issue. The SB2040 has no provision for TACH signal, although it does support a PWM fan. In this case, one would use AGND, PWM(1) and 24v, for a 24v fan, with no fan speed monitoring. 

The lack of any available fan speed monitoring is the one thing I really dislike about the SB2040.

[RainerBoden]

8 hours ago, mvdveer said:

suspect the hart toolhead breakout is different to that of Mellow.

It is actually the same. I compared them and the pinout is the same. If i remember correctly, on some Mellow document site they state its the same board.

 

5 hours ago, kharrisma said:

Can I ask exactly which fan you're using? 

Im also using a 2 wire fan.

I tried frequencies of 20, 25 and even 33kHz, but then the fan just stalls at everything lower than 30-40%.

[Nurgelrot]

I used these 5015's on most with the Fly toolboards. (sb2040v2-3 and SHT36RRF/v3) no issues. But as you can see they are 12V and a sunon maglev 3wire for the Hotend fan (too hard to get a pictures).