USB-6289 OEM temperature problems

[Bill_Jacobs]

Hi Everyone,

I'm working on developing a device that uses a USB-6289 OEM board within an enclosure.  Also in the enclosure is a signal conditioning board and a power supply board.

The USB-6289 OEM runs quite hot.  It was calibrated at 41 or 42 deg C and if I understand the specifications correctly, it should not be allowed to get above 45 deg C.

I monitor the temperature with software and it rapidly shoots up above this threshold.  We built a fan into the enclosure but this seems to not be enough.

I'm looking for tips on how to keep it cool enough.  Any ideas would be greatly appreciated.

Thank you,

Bill

[sandheep]

Wondering if anyone else has had this issue...I just got my USB-6289 OEM and after a few hours of use, I hadn't noticed how hot it gets--with my IR temp sensor, I clocked the heatsink at 80C.  NI-MAX reported it at over 100C with no enclosure (but a PCB mating to it).

I've been using all sorts of USB OEM DAQs from NI for years and have never had this issue.  Is this common with the USB-6289 OEM?  Or is this unit defective? 

The way the heat sink is situated with respect to the 34 and 50 pin connectors (while sandwiched between the DAQ and a mating PCB), there aren't  a lot of good ways to ventilate this.  A 15CFM blower pointed at the heatsink could only get the reported temp down to about 55C, and a 50 CFM tubeaxial fan gets it down to around 36C, but that's still outside of an enclosure (and this fan is wailing--55dB).  Two 27 CFM fans pointed at the heatsink takes it down to about 35C (and gets the noise down to 31dB). 

I guess I've answered my own question here--if you are using the USB-6289 OEM, it needs to be very well ventilated to keep the temps within spec.  I'm curious to know if the regular USB version (which is enclosed) runs this hot.