Heat and pressure build-up in waterproof enclosure

I am using the H7+ cam in waterproof boxes outdoors, and since I will confirm their design soon, I am wondering whether I should worry about pressure equalisation and heat dissipation.

The board generates heat and it will be in a half-litre volume box that contains a Lithium battery (10000 mAh). The board will be 5 mm away from the box wall. Should I have a heat sink, maybe a simple metal piece on the inside of the box wall, or something more elaborate?

Should I equalise pressure with a dedicated vent in case the device will be used at different elevations or under different weather conditions?

You don’t really need to do this. The STM32H743 doesn’t generate that much heat. Thermal conductive radiation will be enough.

That said, you can only test if this is necessary yourself. I can’t give you an answer on this. Only that you don’t need to worry about heat issues and the processor crashing. E.g. if the box was a vacuum enough heat will disparate through the PCB via the standoff holes.

excellent, thanks Kwabena!

You may also want to consider the thermal effects of a closed box being out in the sun?
This can add a significant amount of heat to the system.
A simple sunshade is all that is required to counteract this. Or an extra layer on the outside of the box stood off the closed box enough to allow air and heat to flow between. (A 1cm gap is a good aiming point.)
The pressure difference between the outside and the box is unlikely to be a problem unless it goes up in an aeroplane’s unpressurised hold. (And you have to be VERY careful to seal a box to be gas tight!) :slight_smile: All the best

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thanks, these are good points! I will use a light color for the box. and place it in the shade if possible.