Dust buildup on the chassis may result in electrostatic adsorption, which causes poor contact of metal
components and contact points, especially when indoor relative humidity is low. In the worst case,
electrostatic adsorption can cause communication failure.
Table 1 Dust concentration limit in the equipment room
Dust diameter ≥ 5 μm
The equipment room must also meet strict limits on salts, acids, and sulfides to eliminate corrosion and
premature aging of components, as shown in
Table 2 Harmful gas limits in the equipment room
All electromagnetic interference (EMI) sources, from outside or inside of the switch and application
system, adversely affect the switch in a conduction pattern of capacitance coupling, inductance coupling,
electromagnetic wave radiation, or common impedance (including the grounding system) coupling. To
prevent EMI, take the following actions:
If AC power is used, use a single-phase three-wire power receptacle with protection earth (PE) to
filter interference from the power grid.
Keep the switch far away from radio transmitting stations, radar stations, and high-frequency
Use electromagnetic shielding, for example, shielded interface cables, when necessary.
Route interface cables only indoors to prevent signal ports from getting damaged by overvoltage or
overcurrent caused by lightning strikes.
The 5500 EI and 5500 SI switches are Class 1 laser devices.
Do not stare into any fiber port when the switch has power. The laser light emitted from the optical fiber
may hurt your eyes.
Concentration limit (particles/m³)
≤ 3 x 10
(no visible dust on the tabletop over three days)
Maximum concentration (mg/m