Environment: Operating temperature, 0–50°C
Those people were using the Pi 1B which has a different USB chip to the Pi 3B+.kaksi wrote: ↑Tue Jan 08, 2019 2:23 pmThat's why I expressly specified in what temperature it had been. However, many people used it such an environment, i.e.
What I am interested in are the risks.
Came here to say this.
As well as that if you can add some insulation around the Pi that might well mean it keeps itself warm enough to not have any issues. You could always just put the camera outside the insulation (or even outside the box) with a small slit made for the cable to pass through. Of course this could lead to overheating issues once it starts to warm up.
I found 0-50° operating temperature for 3B+, and 0-40° for 3B in datasheets.
To the best of my (limited) knowledge, the operating temperature range of the Pi is based on the component specs and the figures are--not surprising--conservative. They are not based on actual tests. This leaves us with anecdotal evidence and that evidence suggests that, on the lower end, the Pi actually capable of functioning well below the specified lower temperature. And--FYI--the Pi that was tested at Cern "failed" in what they were hoping it could do. They wanted to see if it would run at -200C. -180C is still pretty impressive for a piece of consumer grade electronics, though.HermannSW wrote: ↑Tue Jan 08, 2019 7:10 pmI found 0-50° operating temperature for 3B+, and 0-40° for 3B in datasheets.
I found no similar data for the earlier Pi models.
What I find really disturbing is that this information (datasheets) is not available officially:
https://www.raspberrypi.org/documentati ... /README.md
Anyway, anyone using Pi outside of operational temperature range is doing that at his own risk. Doing so is not supported. That is what operating temperature is provided for in datasheet. You can get lucky, but there is no guarantee. That is the same for Raspberries as for any other product.
you're aware of 'tin pest' (aka alpha tin or gray tin). I don't know what alloys you use for soldering but it's definitively not always only a condensation issue.. It may not fail immediately but it can happen over time...
some thoughts here. Solubility of gases in other gases (and water vapor is a gas) depends on temperature simple rule: the warmer it is, the more water vapor is soluble in air so if it looks dry at room temperature vapor will condense at lower temps are there you'll have condensation issues. If you wear glasses you might know this phenomena if you enter a warm room on a cool day (water will condense on the cold surface of your glasses) the same can be observed by 'burning' a glass at room-temperature with a lighter (burning hydrocarbons generates carbon dioxide and water, the water of this 'hot gas mixture' condenses on the colder glass, don't do it on newer plastic coated classes! ). The silica bags often delivered with electronics might help to prevent this a little bit (at least for a short time).
Actually, pure water isn't very conductive by itself, and doesn't wet metals so doesn't provide a path for current to flow.
The outside ambient temperature might have been -42C, but I am not convinced the Pi or the camera was.
It probably doesn't get inside and into contact with the silicon, but there's all those legs with gaps between, and some of them are in quite high-impedance circuits. It wouldn't take much polution to stop them working properly.
As well as any electrical issues water might pose there's also potential mechanical issues. As water freezes it expands so could physically damage traces, components and contact between them. If the board was running and ambient temperature was only a few degrees below zero I doubt anything would freeze on the board. If the board was enclosed so any moisture was kept to a minimum then that would probably also reduce the risks of damage from freezing water.
I was surprised on that when it happened to Pi Zero mounted on RC airplane and landing in wet grass: