Troubleshooting - Fan running at 100%
Finished my first HM build, v.4.3. Not having soldered for over 20 years, I'm very happy with the result! Installation and booting up and accessing webGUI via my rPi3 works great, thermocouple and temp probes are all working, however the fan is running at 100% directly form start up. I have switched to pulse, running the fan manually but I can't get the fan to run as intended.
I have read through this thread:
https://tvwbb.com/showthread.php?70400-2nd-Build-Fan-running-100
With the following measurements, for pulse mode:
I have thoroughly checked the board for shorts or poor solder fil but it looks good to me, have also cleaned the board from flux and dirt.
RalphTrimble's measurements as per post #5:
Q1 to pin 5 ATMEga reads 0V regardless of fan speed (in pulse)
Q3 to Q1 reads 0V regardless of speed
This is the same with pin 5 bent out of position.
I did not follow where to measure Ralph's other post with the schematic picture, but I do have 12V on one of the Q1's legs
I did the continuity test as Bryan explained and got the correct result.
Unfortunately, my knowledge about the logic behind on how the board is created and supposed to work is limited, but I suspect that the problem lies in volt regulation somewhere, as the fan seems to be getting 12V all the time.
Any ideas where to look next?
Finished my first HM build, v.4.3. Not having soldered for over 20 years, I'm very happy with the result! Installation and booting up and accessing webGUI via my rPi3 works great, thermocouple and temp probes are all working, however the fan is running at 100% directly form start up. I have switched to pulse, running the fan manually but I can't get the fan to run as intended.
I have read through this thread:
https://tvwbb.com/showthread.php?70400-2nd-Build-Fan-running-100
With the following measurements, for pulse mode:
I have thoroughly checked the board for shorts or poor solder fil but it looks good to me, have also cleaned the board from flux and dirt.
RalphTrimble's measurements as per post #5:
Q1 to pin 5 ATMEga reads 0V regardless of fan speed (in pulse)
Q3 to Q1 reads 0V regardless of speed
This is the same with pin 5 bent out of position.
I did not follow where to measure Ralph's other post with the schematic picture, but I do have 12V on one of the Q1's legs
I did the continuity test as Bryan explained and got the correct result.
Unfortunately, my knowledge about the logic behind on how the board is created and supposed to work is limited, but I suspect that the problem lies in volt regulation somewhere, as the fan seems to be getting 12V all the time.
Any ideas where to look next?
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