FlightAware Discussions

Keeping the RPi cool does make a difference

Unless it is a really low tech fan, the efficiency will drop if the rotation is reversed.

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Yeah it was sort of nerdy wasn’t it. Hey… as long as I believe my own BS, all is good. :upside_down_face:

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It’s a spare part in the British car industry.

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Lucas - The prince of darkness.

Somehow I’m not surprised that it was the British car industry that solved the problem with the magic smoke :joy:

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If the Brits are still using positive earth like that in my last British car circa 1958, then …

Not for the last 50 years :slightly_smiling_face:

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My results after using a passive heatsink.
Note that it is behind a dresser in my bedroom
I have to cover it as the GNSS hat flashes once per second for PPS(Accurate NTP) so it doesn’t get a lot of fresh air.

image

From experience, changing the orientation of the Pi can make a helpful difference. Operating the Pi on the side or end helps convection air flow. The little top mounted fans are also a big improvement, especially when run on 3.3 volts instead of 5.0. Quieter and about half the power consumption on the fan. All depends on what you are running on the system pushing the temps up. You can test the cooling effects by just changing orientation or directing a fan at the board to let you know what to do for your own situation. Have fun.

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I designed my own drone to maintain a GPS hover over my feeder farm. The attached picture was taken as its landing gear was down to perform a routine battery recharge.

Nice UAV / Drone.
How quiet is that fan?
My tangle of SBCs and cables live in an old outside boiler room (more like a cupboard really), the auxiliary fan makes a bit of a racket.
Can the shocking pink LEDs be disabled.

How quiet is that fan?
Can the shocking pink LEDs be disabled.

It is a very quiet low speed fan. I bought two of them from a local surplus electronics store.
It is for 12v and I run it at 7.5v. That is the lowest voltage will run at and still restart on its own
if the AC power recycles. The LED leads could be snipped, but it makes for a good nightlite…

This picture is of the original prototype of a lawn sprinkler monitor/logger I built several
years ago before the Pi3B+ came out. The production model is located in my garage
and gets very hot in the summertime. It also gets an input from a reed switch on a water
meter inline with the sprinklers to calculate flow rates for each valve zone. It also monitors
for leak detection. That system uses the same fan for cooling.

That fan also came from the same surplus store. It is all metal and has mounting tabs
perpendicular to to the board. It draws only 70mA. After seeing the quality of the fan I went
back to the store and bought his entire stock of six. I bought these years ago before small form
factor fans became available. The red LED is for heartbeat and the yellow is a fan on indicator.

The Pi run 40 degrees F over ambient. When the yellow LED comes on I know it is over 90
degrees in the garage.

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Raspberry Pi 3B+ at the MTG site. Originally we had a generic fan mounted in a corner blowing over the Pi. It seemed to cope last year but for some reason it’s been running a lot warmer over the last few months, despite the fact that the outside air temperature hasn’t been as hot as last year. It even hit thermal throttle a few times.

Now it’s a Pimoroni fan shim and the temperature has instantly dropped by at least 16°C

That’s a really low temperature. My Pi 3B+ sitting in air conditioned 23ºC space with a case fan stays about 55ºC.

CS5Temp

That’s mine for the ast 24 hours. The first graph is the outdoor device (Pi3B)with removed cover of the case because it’s warm today. No active cooling, only the heat sinks on the chips

The second one is the indoor Pi4 with passive Armor case

This is what’s happened over the last year. We had a decent summer in 2019, warmer than it’s been this year so I can’t explain why the temperature had slowly drifted up. The old fan was still spinning and it appeared fine.

Dust on the fan blades will greatly reduce airflow. BTDT

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How does dust get into a box that’s 30ft up in the air and is almost completely sealed? :smiley:

If the fan has a fresh air intake dust will attach to the fan aided by ambient moisture. I know in Florida we’ve had a load of Saharan dust dump on us over the past few weeks. The sky is very hazy.

(Dust will find a way. Look at the heat exchange coils on your refrigerator.) :grinning:

It doesn’t, it’s in a box which is sealed apart from one tiny pinprick hole.