Print cooling fan just run if set to 100%

CarlJonas

Hey guys, I have two printers, both run with an Radds board an have the same Firmware. The print cooling fan runs perfect on the one printer, i can adjust the speed but on the second printer the fan just run if I turn the speed to 100%. Can you help me please? There is one difference between the printers. The one which runs fine has an original arduino due, the one with the fan problem has an clone arduino due. Is this the reason or do i have a falty radds board?

Best Regards
Cai

Repetier

Fans get a PWM signal with 15-30 Hz depending on firmware version used. Not all fans work with such frequencies, some have a speed signal that needs other frequencies. If it works for 100% arduino and radds are working, otherwise it would not have started at all. What happens if you go down with speed after it started? While it normal that until 30% many fans do not start it should be possible to go down to 90% when started. Or you have a fan that requires other frequencies. They normally have 3 cables instead of 2.

CarlJonas

Hey, thank you very much for the fast reply. When i turned the fan to 100% it runs at full throttle, when I then switch it to 75% it stops turning. When i use the repetier host and set the fan speed to 90% it turns much slower, below 90% it doesn't turn anymore. I use two sunon 30x30x10 fans with two wires (plus and minus), is there a possability to adjust the sector of fan pwm in the firmware?

Best Regards
Cai

Repetier

No, host always scales from 0-255.

Have you tried switching the 2 fans to see if the good fan also stop on the bad radds? Maybe fan has just more friction. Also watch out for polarity of course.

CarlJonas

ok i understand, i tried another fan and that worked perfekt, looks like the two sunon in parallel doesn't work as they should