Installing System Boards
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3.
Within five minutes, replace with a new sFU-40V and place and tighten the four screws.
4.
Listen for proper sFU-40V fan operation.
7.7.2
Horizontal Fan Unit (sFU-40H)
The sFU-40H horizontal fan unit, shown in the following figure is part of the 4700 air cooling
system; it provides cooling of the Fabric Boards. It includes eight fans with fan speed control;
fan speed is dynamically controlled as a function of temperature.
LED indications provide an onsite report regarding the operating conditions of the air cooling
system modules, and provide an alarm indicator in the event of a high temperature condition.
To replace the sFU-40H horizontal fan unit:
1.
Loosen the four screws that secure the sFU-40H horizontal fan unit to the chassis.
2.
Remove the sFU-40H horizontal fan unit by sliding it out of the chassis.
3.
Replace with a new sFU-40H horizontal fan unit and tighten the four screws (within five
minutes).
4.
Listen for proper fan operation and check the LEDs.
Chapter 8