Experimental Physics and
Industrial Control System

Joe Sullivan <[email protected]> · Wed, 19 Aug 2009 09:44:43 -0500

Note to DeltaTau UMAC system users (based on experience with
a cooked PowerPMAC CPU):

The passive cooling design of the DeltaTau UMAC crates seems marginal
for the requirements of the PowerPMAC CPU. For this board to
remain within nominal temps (~60C) it requires ventilated top and bottom
cover plates on the CPU slot and adjacent slot (left side).

The UMAC racks shipped with PowerPMACs are configured correctly
(see picture). http://www.aps.anl.gov/bcda/Images/ppmac_rack.jpg

The problem is when the PowerPMAC is installed in a preexisting
UMAC crate that shipped with another controller board (ie. Turbo UMAC).
These crates have solid top and bottom cover plates that need to be
replaced (or removed).

The standalone PowerPMAC board ships with one set of ventilated
cover plates for the CPU slot but not the adjacent slot. The CPU
does overheat in this configuration (> 68C).
           http://www.aps.anl.gov/bcda/Images/umac_top.jpg

The solution is to either acquire another set of ventilated cover
plates or to remove the plates altogether. This setup does run
effectively.

http://www.aps.anl.gov/bcda/Images/umac_fixed.jpg

Additional Note: Care should be taken to mount the UMAC crate
in it's natural horizontal position (front facing out) to allow
for maximum air circulation.

--
Joseph Sullivan
[email protected] <> 630-252-8657
Advanced Photon Source
APS Engineering Services Division
Beamline Controls & Data Acquisition Group

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System