Electronic output 1

[82james82]

Hi

I'm looking for information on the temperature output of electronic circuits. I am to develop cooling methods but need to know what sort of temperatures i am dealing with.

I'm looking mainly at vehicles but only need a rough idea of what temperatures are seen.

Cheers

 

[melone]

A good ballpark for automotive grade components would be from 85°C -> 125°C. The reason for such a large range is due to mounting location in the vehicle. If the component is mounted inside the passanger compartment, the max temperature will be less severe, than if the component was mounted in the engine compartment.

Unfortunately, I don't have a good number for you if the component is actually mounted to the engine itself....

 

[82james82]

thanks

What I am really looking for is just the output from the electronics because i have lots of data on engine temperature etc.

thanks again

 

[IRstuff]

Circuits do not have "temperature output," they have heat output.

Heat from circuitry will range from milliwatts to tens of watts, depending on the application.

TTFN

 

[82james82]

ok yeah sorry for the confusion.

I'm relatively new to the field of electronics in regard to the heat output.

the heat outputted from a circuit in a car will only be a few watts though?

thanks

 

[IRstuff]

Depends on the circuitry.

The Holley electronic ignition module draws a maximum of 40A, presumably at 12V:

http://www.holley.com/HiOctn/ProdLine/Products/IS/ISIC/800-500.html

TTFN

 

[jraef]

Typically if you look at the power consumption of a device and look at the efficiency, you can determine the heat output as the difference. However if you are in a closed area where the work performed by the device is in the same environmet as the device, the heat output is essentially the power rating of the device.

For instance, if you have a 400W stereo amplifier under the seat of the car, and the stereo and speakers are inside the car as well, all 400W is going to be dissipated into the car interior somehow. But if you have a 200W power supply under the dash that is powering an ignition computer in the engine compartment, and the power supply is 80% efficient, only 40W of heat is being dissipated into the interior. The rest is going into the engine compartment.

I just made these numbers up of course. You will still need to do some more research as to what is being used in cars, and of course that varies greatly as well. My Chevy does not have many do-dads inside, but my brother's Mercedes has more electronics than most small convenience stores!

"Venditori de oleum-vipera non vigere excordis populi"

 

[nbucska]

I would think the electronics must work even when the
engine is cold, so I would put the lower limit to -40
C (-40 F)


<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032

 

[VEBill]

In parts of Canada, -50C (not including wind chill) is not unknown. -40C is pretty the expected low in many cities.