Berd-Air - poor pwm response with ez switch

o_lampe

@ockray83
Just to be sure, did you check the jumper for the PWM fans is at the 'Vin' position?
Even if we'd know which type of MOSFet it is, we don't know if the optocoupler inverts the signal.

I believe it's common to switch a MOSFet to GND. Switching to Vin requires a bootstrap circuit but I don't see any.

ockray83

@o_lampe The jumper is in the Vin position.
The MOSFet is identified as F5305S
The coupler appears to be an EL817
I'm not certain if that helps at all.

It looks like makerhive sells all their berd air kits with these switch boards now. If this were a common issue I think I would find it in forum posts somewhere. Maybe I have a defective board/pump?

Side note, I did try running a print at 100% speed, just to see what happened and I noticed that while the heated bed output light was illuminated, I got a slight change in pitch from the pump and checking with a meter, the power going to the pump was dropping off by .08vdc and rising back again once the light was out. At the moment the two are sharing the same PSU.

Update: makerhive got back to me and are sending me a new switch, they believe mine is defective. I should get it in a few days.

uk25

@ockray83 said in Berd-Air - poor pwm response with ez switch:

Update: makerhive got back to me and are sending me a new switch, they believe mine is defective. I should get it in a few days.

Just got the same problem... Did you already receive a new ezswitch from makerhive and did it really solve your issue?

ockray83

@uk25

Its been a while since I've been able to mess with my printers, sorry for the delay. I got the new switch from MakerHive installed and my control has not really improved. I get a small 'controllable window' within the S0-S255 range which I can shift with frequency changes, but nothing I've done has widened the span of that window. Anything below the controllable range results in the offensive buzzing sound with little to no output of air from the pump. Anything above the controllable range results in no change in output (S200-S255 may output the same amount of air, for example). I also installed a diode across the terminals as recommended in other forum posts, with no change in performance. If you figured your issue out, please let me know as I am out of ideas to make this work.

Dougal1957

@ockray83 have you tried adjusting the PWM Frequency in RRF I use a bird air system (have done for years) but I used a power expander from Reprap.me on mine and don't have any issues. Check M950 Qnn parameter

uk25

@dougal1957 said in Berd-Air - poor pwm response with ez switch:

@ockray83 have you tried adjusting the PWM Frequency in RRF I use a bird air system (have done for years) but I used a @dougal1957 on mine and don't have any issues. Check M950 Qnn parameter

Thanks, @dougal1957 for another lead. Looks like the power expander hasn't optoisolator as utilized in e-z switch controller. So maybe that's the main reason for such poor pwm control.

Fred-Y

I have the set from Makerhive with the EZ switch on one of my printers, below is what I use in the config.g

M950 F0 C"fan0" Q100                                ; create fan 0 on pin fan0 and set its frequency
M106 P0 S0 H-1 C"Part Fan"                                      ; set fan 0 value. Thermostatic control is turned off

The pump is fairly quiet and I can adjust the speed.

I bought that kit 2 or 3 years ago so they might have made some changes.

ockray83

@fred-y
It looks like the m950 command isn't supported by my board's current firmware (2.05.1). I haven't updated this thing in a long time. I'll have to go through the update and see how it does with the commands you've provided.

uk25

@ockray83 You can just use F100 parament in M106 on the earlier firmware version to set the frequency. Currently, I'm not near my printers and can't try that.

Also, have to mention that previously, everybody suggested using F about 25500, but now Makerhive advises to set it extremely low. Hope that helps.

Phaedrux

@ockray83 said in Berd-Air - poor pwm response with ez switch:

@fred-y
It looks like the m950 command isn't supported by my board's current firmware (2.05.1). I haven't updated this thing in a long time. I'll have to go through the update and see how it does with the commands you've provided.

If you still have access to DWC. Upload these 3 zip files, one at a time in the system tab. Don't extract them first. Reboot after each. Use M115 in the gcode console to verify the firmware has been applied.
https://github.com/Duet3D/RepRapFirmware/releases/download/2.05.1/Duet2Firmware-2.05.1.zip
https://github.com/Duet3D/RepRapFirmware/releases/download/3.0/Duet2and3Firmware-3.0.zip
https://github.com/Duet3D/RepRapFirmware/releases/download/3.3/Duet2and3Firmware-3.3.zip
That will get your firmware and DWC up to date.

You can see the change logs here:
https://github.com/Duet3D/RepRapFirmware/wiki/Changelog-RRF-3.x

For your config, might be a good idea to run through the configurator tool and generate a fresh set for RRF3.
https://configtool.reprapfirmware.org/Start

Backup your existing config files in the sys folder in case you want to switch back to RRF2. It’s easy to switch back and forth, just upload the zip file for the version you want and then upload your config files.

These documents will come in handy during the conversion.
https://duet3d.dozuki.com/Wiki/RepRapFirmware_3_overview
https://duet3d.dozuki.com/Wiki/Gcode