Fan Speed Adjustment
When the system is fully configured, fan speeds are adjusted according to temperatures
reported by the temperature sensors on the LPUs, SPUs and MPUs.
general fan speed adjustment principles.
Table 1-33
Fan Speed Adjustment Principles
Ambient
Temperat
ure
Rotationa
l Speed
Noise and Dissipation Standards
-5°C-
+27°C
(23°F -
80.6°F)
Low (50%
rotational
speed)
When fans rotate at a constant low speed, the noises meet the
ETSI standard and the fans meet heat dissipation requirements
of a fully configured system.
27°C-45°C
(80.6°F
-113°F)
Linear
variation
The fan speed is adjusted smoothly and linearly, without a
sudden increase in volume.
Over 45°C
(113°F)
High
(100%
rotational
speed)
Fans rotate at high speeds to meet heat dissipation
requirements.
1.3.5.3 Air Filter
This section describes the appearance and features of air filters.
The air filter of the USG9520 is located on the left rear of the chassis, as shown in
.
Figure 1-43
Air filter on the USG9520 air intake frame
HUAWEI USG9500 Series
Hardware Guide
1 Hardware Overview
Issue 03 (2017-12-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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