Huawei OptiX OSN 8800 Hardware Description page 85

OptiX OSN 8800/6800/3800
Hardware Description
Table 4-55 FAN speed mode
FAN Speed
Mode
Auto Speed Mode There are four areas (A, B, C, and D) in each subrack. The boards in
Adjustable Speed
Mode
Each OptiX OSN 8800 universal platform subrack is divided into four partitions in terms of
heat dissipation. The subrack adopts one fan tray assembly to implement partitioned heat
dissipation. See
Issue 01 (2016-03-10)
Description
the areas overlap and the heat generated by the overlapped boards is
dissipated to the two areas where they are located. Fan speed in each
partition is regulated automatically according to the temperature of the
boards in the partition where the fans are installed.
Lower than 25° C (77° F): the fans run at low speed.

Higher than 45° C (113° F): the fans run at high speed.

25° C to 45° C (77° F to 113° F): The fans automatically adjust their

rotation speeds. This mode can reduce noise and is power-saving.
Fan speed in each partition is independently regulated.
The fans run at full speed if the speed regulating signals are abnormal.
When one fan becomes faulty, the other fan in the same area adjusts
the fan speed based on the temperature reported by the board. When
two fans become faulty, all the remaining fans run at full speed.
Six fan speed modes are available: Stop, Low Speed, Medium-Low
Speed, Medium Speed, Medium-High Speed, and High Speed. You
can set the fan speed manually. In Adjustable Speed Mode, the fans in
all partitions run at the same speed and do not support the partitioned
manual fan speed adjustment.
Figure 4-35.
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4 OptiX OSN 8800 Subrack
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