Using PXI chassis in Ex 'd' enclosures

[MalcolmSharp50]

A recent application we are investigating would involve the mounting of a PXI chassis (e.g .a 4 slot 3U universal power supply) in a Ex 'd' (flameproof) type enclosure. As the enclosure is sealed the PSU and board cooling fan will basically be moving the same air around; the air cooled only by contact with the interior surface of the enclosure. Before I get involved in the details of calculating the thermal side of this approach I was wondering if any other users have had experience of this kind of problem, run into any 'gotchas' or explored other solutions such as mounting the main heat generating components directly (thermally) to the inside of the enclosure.

Any pointers etc. gratefully received!

Thanks and regards,

Malcolm Sharp

[Ian Colman]

Hi Malcolm,

Unfortunately no one in the technical support office here at National Instruments UK has any experience with using a PXI chassis in a heated confined space so the only advice I can give is to make sure that you work within the hardware’s recommended operating range, which from the datasheet is 0 ^oC to 50^oC for the PXI-1031 Chassis. If you have any more specific questions regarding any aspect of your system that I can help you with, please don't hesitate to ask.

Best of luck with your application and apologies for not having more of an input for you,

Ian C.
Applications Engineer
National Instruments UK

[MalcolmSharp50]

Ian,

Thnaks for the quick response. It was a long shot but I guess I'll jst have t odo the themal modelling to ensure that the air temperature in the enclosure doesn't get close to the 50 degrees C limit.

Thanks and regards,

Malcolm Sharp