By now, others have told you the name: environmental oven(or chamber).

The oven you need depends on:
a) volume of boards to be tested (cubic meters, inches, etc.)
b) temperature range - how cold to how high
c) required rate of change of temperature
d) amount of electrical power devices under test require

Chambers are available that use liquid nitrogen to go very cold very
quickly. Very $$$. You will have to decide what you need here.  If your
needs are somewhat modest, you can build your own.

My company has a need to test boards from 0 C to about 50 C.  We purchased
an upright freezer from Sears (about $250).  The heater is provided by 200
to 300 watts of lightbulbs.  The controller is an a/d io card (National
Instruments or clone) stuck in an old 486 pc.

Here is a secret on how to make it work.

Don't attempt to regulate the freezer.  The compressor won't like it. Just
turn it on and leave it on.  Regulate the temperature by adding heat.
Also, open the back of the freezer and pull out the temperature sensor
where it's attached to the freezer compartment. Just bend it out into the
air so it never tries to cycle the freezer.  Add a small fan to stir the air.

Setup your temperature sweep to go cold and ramp up to your hot
temperature. (btw, don't try to go much above 50 C; you may melt the
plastic liner of the freezer).  The pc should be setup to not only control
the temp but cycle power to the test boards and log data for you.  You will
need to know how to write a simple pid control loop program.

Run down to at least 5 degrees colder than the bottom of your test. Soak
for some period of time. Then turn on power to your boards. Now begin
ramping the temp up at your required rate.  Once you get up near room
temperature, you can turn off the freezer and continue on regulating heat
with just the heater (light bulb).

We have such a setup as described running and have used it for around 10
years.  It works perfectly for our needs.  As usual, ymmv.

Good luck!
Tom


At 12:04 PM 1/16/2004 +0200, you wrote:
>I don't know if this is EE or OT; however, I need a box where I can set the
>temprature inside it (within a certain error margin) and keep it the same
>temprature (again within a certain error margin).  I will use this box to
>put some electronic boards into temprature tests.
>
>Is there a name for this "box"?  Any recommendations?

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