Checking the Installation Site

The S2700, S3700, S5700, and S6700 series switches (except for the S5720I-SI) must be installed in indoor equipment rooms. The S5720I-SI series switches can also be installed in outdoor cabinets. Table 1 describes the requirements for the installation site.

**Table 1** Requirements for the installation site
Item	Requirement
Cleanliness	The installation site must be clean, dry, well ventilated, and free from leaking or dripping water and dew.
Dust	The installation site must not have an excessive amount of dust. A buildup of dust may cause electrostatic discharge on the chassis and impair electrical connections, which will reduce the service life and may cause failure of the switch.
Temperature and humidity	The switch must be installed in a temperature-controlled environment where the temperature and humidity are within specifications. For the operating temperature and relative humidity ranges required for your switch, see the Hardware Description. In environments where the relative humidity exceeds 70%, use dehumidifiers or dehumidifying air conditioners.
Corrosive gases	The installation site must be free from acidic, alkaline, or corrosive gases.
Airflow clearance	Leave at least 50 mm (2.0 in.) clearance around the switch for heat dissipation. Do not install a switch with its air intake vent facing or close to the air exhaust vent of other devices.
Service port surge protection	If power and network cables of a switch need to be routed outdoors, bury them underground or put them in steel pipes to protect the switch from lightning strikes. If the network ports on the S5720I-SI series switches are connected to devices on a street pole, no surge protector needs to be installed. If the network ports are connected to devices on a tower, a network port surge protector must be installed. To protect network ports from lightning, use 8-line surge protectors or Huawei certified 4-line surge protectors. Connect the IN ports to terminals and the OUT ports to network ports of the switch. If fiber reinforcing ribs are used, ensure that they are properly grounded to protect the switches from lightning.
Power supply surge protection	When installing the S5720I-SI series switches in outdoor cabinets, ensure that the following requirements are met: AC switch: If the 220 V mains supply is used, install a 20 kA surge protector between the power port of the switch and the mains. If power is supplied by an isolated inverter near the outdoor cabinet, no surge protector needs to be installed between the power port of the switch and the inverter. DC switch: An isolated power supply must be used and placed in the same outdoor cabinet as the switch. Surge protection is required for the power input of the outdoor cabinet. The surge protector, power supply, and switch must be equipotential. The outdoor cabinet must be properly grounded and the grounding impedance must be less than or equal to 10 ohms. If a DC switch is connected to the PAC-260WA-E or PAC240S56-CN power module that is powered by the 220 V mains, install a 20 kA surge protector between the power input port of the PAC-260WA-E or PAC240S56-CN and the mains. The 20 kA surge protector and S5720I-SI switch can be decoupled using 5-10 m power cables or decoupling inductors. For details, see "WLA220W01-20kA Surge Protector" in the S5700 Series Switches Hardware Description. In all installation scenarios, switches, cabinets, independent power modules, and surge protectors must be separately grounded.