Hello All , i'am studying for a project that will be in our car's accessoires shops, the main idea of it ,is about lock , unlock, and more functions for the car , it will be by android applictaion and Arduino UNO (with BlueTooth sheild )
Now there are two questions
first , what is the maximum temperature can Arduino bord loads? so the board will be surely in the car , and in our hard weather (saudia arabia) the temperature of the Arduino board will be very high ! (sometimes temperature up to 55c)
is that temperature causes problems for Arduino ?
Second, this Arduino will works maybe for 24\7 hours\days , is there any problem about that ?
Electrical Characteristics
28.1 Absolute Maximum Ratings*
Operating Temperature.................................. -55°C to +125°C
Storage Temperature ..................................... -65°C to +150°C
That's only the processor.
Also have to consider the USB/Serial chip, the 5V & 3.3V voltage regulators, the op amp, the power-switching FET, the LEDs, the crystal and resonator.
So its more than just 1 chip.
to increase working temperature, u need hardware mod, replace electrolytic capacitors to non electrolytic capacitors, means capacitors has same size of arduino and cost same or high than arduino. You get what u pay for.
55C is only 131F, I think cars can get much hotter than that sitting in the sun during the summer.
Most commercial electronics are rated 0C to 70C (158F).
If the ambient air temp is that high and then power is applied, the electronics can be even higher.
Caps like might be found on the Arduino input power pins
47uF, 25V,
are good for 1000 hrs at 85C (41 days)
so a summer spent baking in the sun might shorten their life.
Electrolytic Capacitors will decline capacitance at low temperature, at –40 °C could be 20% -40% decline, for power supply filter application might be OK. but still need count at the design.
I recall buying a brand new Ford Thunderbird (I loved that car) around 1986 on a Friday night. That weekend the family took a trip somewhere and when we got back one of the three kids (no one would fess up) had left a small box of crayons on the back window ledge. Next time I got in the car I smelled a strange odour and discovered that the crayons had melted in it's box and ozzed out into a puddle all over a 6" area of the rug type material used on the ledge. Boy was I pissed, and cleaning as I could there was forever a rainbow hue left over to remind me of that first weekend in my new car. I didn't yell at the kids (I'm not much of a yeller type) as how were they to know that crayons melt inside cars parked in the sun, hell I didn't even know that. Live and learn I guess.
I suspect the arduino will work OK inside a car, but watch out for crayons.
Crayons begin to soften at around 105 degrees Fahrenheit (40.5°C) and they have a melting point between 120-147 degrees Fahrenheit (48.9-63.9°C). Do not recommend keep drawing while person has high fever.
