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I want to use raspberry pi for a vehicle park project. The Raspberry will stay in a metal box and it will never power off. The metal box is waterproof but its in middle of a empty area so it will get really warm under sun and really cold at the winter.

So can I use raspberry pi for a project like this? Can someone give me idea?

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closed as primarily opinion-based by Andy aka, Voltage Spike, Dmitry Grigoryev, winny, brhans Jun 27 '18 at 20:49

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.

  • \$\begingroup\$ You will need a automotive-rated Raspi. \$\endgroup\$ – Long Pham Jun 22 '18 at 9:24
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    \$\begingroup\$ It will never power off → no cold or moisture problems then. If in doubt, put a temperature controlled heater resistor into the box. Don't use a full waterproof enclosure, but a box with a gore-tex breather. That's what is used in automotive. \$\endgroup\$ – Janka Jun 22 '18 at 13:26
  • \$\begingroup\$ idiot test : stick one in a box (wired up with high temperature cable!), connect to it over wifi, and put it in the oven / freezer and see what happens? \$\endgroup\$ – dmb Jun 22 '18 at 13:59
  • \$\begingroup\$ Can you put the metal box in a white-painted wooden box to keep the worst of the heat off it? Polished aluminium will reach 60 °C in the sun, white paint somewhat less. Oh, and the wooden box should not look like a nice place to build a nest for insects. \$\endgroup\$ – Andrew Morton Jun 22 '18 at 14:26
  • \$\begingroup\$ @Janka I second that, a DS18B20 would work well with a power resistor, and the heat would push out moisture. It can also be used to keep temperature around 0-5° in the winter. +1 \$\endgroup\$ – user2497 Jun 23 '18 at 8:34
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I would not be as optimistic as Bimpelrekkie. The moisture will be an issue, but temperature may be one as well. For cost reduction purpose, the Raspberry Pi may use consumer grade electronics, which is usually rated for 0 to 60°C. Automotive grade electronics are expected to go from -40°C to +85°C (ambient) at least (some parts shall work under higher temperatures).

On a RPi3, the CPU is a Cortex-A53 designed for low power consumption and should not overheat first. I don't know the GPU. If the SoC does not fail first, predictable issues may be:

  • Insufficient power regulation as capacitors characteristics changes with temperature
  • RAM corruption due to overheat and insufficient refresh
  • RAM corruption due impedance mis-match (unlikely, as DDR3 performs Zq calibration within the protocol)
  • Flash memory retention issue

Also, the RPi may fail due to vibrations.

Finally, it may also work perfectly fine. I'm just stating that it's not granted, and I'd also like to add that it may vary with the RPi production process. A prototype may work for days, weeks, maybe even months (it may also fail after a few hours), but you can't industrialize anything with a good relation with your manufacturers and a good knowledge of the components you're using.

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In my opionion the Raspberry Pi is not the challenge here, it is just a PCB with electronics like many other electronics.

The challenge is keeping moisture out of the box. That may not be as easy as it sounds. Unless you weld the box shut (not possible as there are cables) moisture will get in somehow, like through the air. With temperature changes air expands and contracts pulling in moist air.

Instead of making the box 100% sealed, leave a small hole at the bottom so any water can be pushed out. This is how many professional outdoor boxes designed for electronics work.

Cold and heat should not be an issue for electronics, most electronic components are designed to work between -30 C and + 80 C, many have an even wider temperature range.

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  • \$\begingroup\$ In CCTV and similar exposed systems, heat is used to prevent moisture from condensing, and to some extent displace it away from sensitive circuits. +1 for the hole in the bottom. \$\endgroup\$ – user2497 Jun 23 '18 at 8:39

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