schroff 10836-060, User Manual

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VXS/VME64x Tower System Product Definition
10836-060
www.schroff.biz 10 R1.1, May 04, 2009
2.5 Thermals
The front boards are cooled by forced air convection through 4 speed controlled
24 VDC axial fans (each fan 125 m³/h (75 cfm)).
Two fans are assembled at the rear panel, two fans are located in the bottom air
plenum.
The air enters the subrack at the lower front into the bottom air plenum and turns
90° upward. As the air passes across the hot components on the Front Boards,
heat is carried away by forced convection. The air exits the Subrack at the top,
is drawn into the upper plenum, turns 90°, and is exhausted out the rear of the
subrack by fans.
The fan speed is controlled by the Fan Control Module (FCM) depending on the
exhaust temperature. The NTC temperature sensor is located above the card
cage.
Figure 5: Airflow
Caution!
To maintain proper airflow, all open slots must be covered with filler panels.
The filler panel should include an airflow baffle that extends to backplane.
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