Ruijie Reyee RG-NBS3200 Series - Page 26

Ruijie RG-NBS3200 Series Switches Hardware Installation and Reference Guide Preparation Before Installation
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2.2.3 Cleanness
Dust poses a severe threat to the running of the device. The indoor dust falling on the device may be absorbed by the
static electricity, causing bad contact of the metallic joint. Such electrostatic absorption may occur more easily when the
relative humidity is low. This affects the device lifecycle and causes communication faults. Table 2-2 lists the
requirements for the dust content and granularity in the equipment room .
Table 2-2 Requirements for the Dust Content and Granularity in the Equipment Room
Dust
Unit
Density
Diameter ≥ 0.5 μm
Particles/m
3
≤ 3.5 x 10
6
Diameter ≥ 5 μm
Particles/m
3
≤ 3 x 10
4
Apart from dust, the salt, acid, and sulfide in the air in the equipment room must also meet strict requirements. This is
because such poisonous substances may accelerate the corrosion of the metal and the aging of some parts. The
equipment room should be protected from the intrusion of harmful gases such as sulfur dioxide, sulfured hydrogen,
nitrogen dioxide, and chlorine. Table 2-3 lists the requirements.
Table 2-3 Requirements for Harmful Gases in the Equipment Room
Gas
Average (mg/m3)
Maximum (mg/m3)
SO
2
0.3
1.0
H
2
S
0.1
0.5
NO
2
0.5
1.0
Cl
2
0.1
0.3
The average and maximum values are measured for a week. The switch cannot be placed in the environment with
the maximum density for over 30 minutes every day.
2.2.4 Interference Resistance
The switch is vulnerable to external interface caused by capacity coupling, inductance coupling, electromagnetic wave
radiation, common impedance (including grounding system) coupling, and conducting wires (including power cords,
signal and output wires). Therefore, note the following points:
 The AC power supplying system is the TN system. The single-phase three-wire socket with protecting grounding
must be used as the socket for the power supply to enable the device’s upper filter circuit to effective filter the
power interface.
 The switch should be far from high-power radio transmitting stations, radar stations and high-frequency and
large-current devices.
 Electromagnetic shielding methods should be applied when necessary, such as using the shielded cable as the
interface cable.
 Cables must be connected to interfaces inside the room to prevent damage to the device’s signal ports caused by
over-voltage and over-current generated by thunder and lightning.
2.2.5 Grounding
A good grounding system is the basis for stable and reliable operation of the device, preventing lightning strokes and
resisting interference. Carefully check the grounding conditions at the installation site according to the grounding
requirements, and perform grounding operations properly as required.