Table 1-11
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 constantly low speed, noise levels meet
the NEBS standard, and the fans meet heat dissipation
requirements of a fully configured system.
27°C -
50°C
(80.6°F -
122°F)
Linear
variation
The fan speed is adjusted smoothly and linearly, without
sudden increases in noise.
Over 45°C
(113°F)
High
(100%
rotational
speed)
Fans rotate at high speeds to meet heat dissipation
requirements.
1.1.5.3 Air Filter
This section describes the appearance and features of air filters.
The USG9580 draws air from the front and exhausts air from the rear. The two air filters on
the upper and lower chassis are identical. To maximize air intake, the filters are fully
perforated. Air filters are fixed to the chassis with fasteners to facilitate filter removal and
replacement.
Figure 1-13
Air filter
The air channel in the SFU slot area is located on the left side of the chassis. The air filter can
be accessed from the front. The depth of the air filter is the same as that of an SFU, and the
height of the air filter is four times the width of an SFU, as shown in
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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