Cleanness
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 4 Dust concentration limit in the equipment room
Substance | Concentration limit (particles/m³) |
Dust | ≤ 3 x 104 (no visible dust on the tabletop over three days) |
NOTE:
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 5.
Table 5 Harmful gas limits in the equipment room
Gas | Maximum concentration (mg/m3) |
SO2 | 0.2 |
H2S | 0.006 |
|
|
NH3 | 0.05 |
Cl2 | 0.01 |
|
|
EMI
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
•Keep the switch far away from radio transmitting stations, radar stations, and
•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.
Laser safety
The HP 5120 EI and 5120 SI switches are Class 1 laser devices.
WARNING!
Do not stare into any fiber port when the switch has power. The laser light emitted from the optical fiber may hurt your eyes.
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