Thermal Chamber with extra closed cabinet (box)

[soumen21]

During thermal testing inside a thermal chamber, I have seen a few guys using another closed cabinet in the chamber. The UUT is kept inside the closed cabinet. Do we really need that extra cabinet inside the chamber? I think the thermal chambers are capable of keeping the inside temperature to the set desired temperature and are uniform throughout the chamber? If so, why is that extra cabinet required in the chamber again?

 

[stenzer]

Hi,

how does this inner cabinet looks like? It might be used to avoid any disturbances of vulnerable/sensitive electronics during a temperature test, induced by the climate chamber itself --> EMC & EMI.

BR

 

[soumen21]

Hi,

how does this inner cabinet looks like? It might be used to avoid any disturbances of vulnerable/sensitive electronics during a temperature test, induced by the climate chamber itself --> EMC & EMI.

BR

It's an aluminium sheet box.

 

[stenzer]

Hi,

you have to decide on your own if you need an additional shielding dependung on your DUT, which kind of tests you are performing and in which kind of signals are you interested (SMPS waveforms or analog sensor readings).

I noticed several times, while testing electronics inside a climate chamber, that the chamber introduces noise espacially when the compressor starts. If you are only intersited in a single and short measurement at a steady temperature, you might turn of the chamber during the measurement.

BR

 

[andre_luis]

You should consider the mass of the device under test and its self heating compared to the chamber itself.
For all test I've made, it was just small board with negligible size and heating, not for power application.