Power supply fan not turning off when print is finished

I have a Neptune 3 plus & octoprint works well but when the print has finished & everything cools down the psu fan still runs. If I'm not using octoprint the fan turns off.

Any help much appreciated


Hello @Rob_Harton !

A PSU fan is neither controlled by the printer firmware nor by OctoPrint. It reacts to the temperature inside the PSU.

Do you have the RasPi connected to the printer PSU?

P.S.:A bit more information about your setup would be appreciated too.
And please: Do not delete the template when you open a help request. Those queries help us to help you.

My apologies for deleting the template. I'm new to asking for help in the forums.

The raspberry pi is plugged into the printer via usb. It's strange because if i unplug the usb cable the psu fan will turn off. If i print from the sd card using the printer no raspberry pi plugged in the psu fan will turn off after about 10/15 mins. If i use octo print the psu fan stays on even after an hr.

That is the only connection that delivers power to the Pi?

And is it the same that delivers tha data from the Pi to the printer?

The pi is powered by mains & then a usb data cable to the printer. The printer doesn't power the pi. I need to get better at explaining things.

Thank you for your help

How is the USB PWR jumper set?

If it is ON, you may try OFF.

Thanks I'll have a look

Something else came to my mind.
Therefore, can you share a zipped gcode file you print in your next post?

EN3P_Calibration Cube.zip (165.9 KB)
Hi i Just sliced this for you to take a look at.

So, my assumption is:

At the end of the print, the steppers are turned off except the Z-axes. This stepper draws enough current to keep the PSU's fan on.

When you print from SD card, at the end of the file, so I assume, the firmware turns everything off.

You can check, when at the end of an OctoPrint print and the PSU fan is still on, go to the OctoPrint Control panel and click Motors off

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I will check tomorrow when I'm home from work. still got 10 hrs left on my current print.
Thanks for the help.

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