12V Fan pin header FAQ

Question

Just for some reference info on the 12V connector

daboone72 · Answer

So on a 4 PIN black is ground and is closest to the key1 button

daboone72 · Answer

And a useful all the connectors reference if you need to figure out others 3 pin etc https faqs noctua at support solutions articles 101000081757 what pin configuration do noctua fans use

colinriddell · Answer

just connected my noctura fan with the noise limiter Works good but I seem to hear it slightly pulse even though it s not a PWM fan and the header isn t pwm either Any ideas

_dhanos_ · Answer

This is how you connect any 3 or pin fan to TPi2

_dhanos_ · Answer

This is odd If you have a multimeter you might try to measure the voltage and see if it also pulses both before and after the noise limiter

colinriddell · Answer

I think this might be because I stuck two limiters before the fan I like how quiet it is but unsure if it s a good idea

_dhanos_ · Answer

The fan can potentially struggle a bit if you lower it the voltage too much This is only a guess though I haven t noticed anything like this but I also haven t stacked the low noise cables

Hizzie · Answer

Another possible Amazon FBHDZVV 4 PCS SATA Power Splitter Y Cable 1 to 1 15 Pin Male SATA to Sleeved 3 Pin 4 Pin PMW 12V PC

Hizzie · Answer

Power Only

colinriddell · Answer

Is there any way to stop the power to the 12v header once node 1 has been powered off

colinriddell · Answer

this was almost certainly the issue btw

_dhanos_ · Answer

There is if you turn off all of the nodes using `key1` or power button in the case if you are using any There s a bug with other ways to control the power like web interface that will not turn off the PSU with the last node turned off We ll fix it soon with the CE firmware

colinriddell · Answer

Thank you

_dhanos_ · Answer

Interesting

colinriddell · Answer

Yeah found out noctura recommend only one limiter per fan Doubling them up works but is a bit dodgy

_dhanos_ · Answer

Good to know thank you

cbceebee · Answer

Just to clarify the 12v fan 2 pin header is just a fixed DC supply no PWM or voltage variation on the 12v pin

_dhanos_ · Answer

The fan header can have 2 4 pins 1 ground 2 +12 V 3 RPM taho this was the controller knows fan speed 4 PWM this way the controller controls fan speed So 2 pin header only has power pins 3 pin header has power pins and can report own speed 4 pin header has power pins can report own speed can be controlled There is also an old standard where you could control fan speed by the voltage on the power pins but this is not used in the TPi2

cbceebee · Answer

thanks for clearing things up

rbenj406 · Answer

Can the 12v FAN header be used to power an external PWM controller for fans on multiple CM4 How much power can this header supply I have 2 CM4 so far and intend to use these heatsink fan combo https www amazon com dp B0B4HCL62K encoding=UTF8 psc=1 ref =cm sw r cp ud dp 7RFVWGZXD5HFN44XWWBE

_dhanos_ · Answer

Yes it can It can supply up to 2A

dadcoachengineer · Answer

Any update on the 4 pin fan pads with no pins soldered

_dhanos_ · Answer

What update do you mean This one is not populated and is not working

dadcoachengineer · Answer

Got it I though I read somewhere that it may be enabled in soft firmware at some point to support a case PWM fan

_dhanos_ · Answer

It cannot since there s more unpopulated parts than just the connector

dadcoachengineer · Answer

Got it Thank you for the clarification