User Guide Modem 3460

3460 Fast’R

1-12

Fan and Deflector Requirements

Forced-air cooling for up to four rack-mounted enclosures can be

provided by fans and a deflector, mounted below the enclosures, to

provide passive, bottom-entry rear exhaust and upward-forced, front-

entry cooling air. Refer to Figure 1-6. The airflow requirement is 80

CFM (2266230 CCM).

For example, three fans rated 117 CFM (202176 CCM) at a static

pressure of 0 inches of water provide enough airflow, when cooling four

enclosures. The deflector ensures that hot air from equipment below the

enclosures does not mix with enclosure-cooling air. The cabinet must

have venting at the top or rear to let exhaust air escape.

Figure 1-6. Cabinet Arrangement

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Three or More Enclosures

Unit 2

Fan Chassis 2

Unit 1

Fan Chassis 1

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