H3C Technologies H3C MSR 20-2X[40] - Manual (Page 18)

11
Gas Max (mg/m 3 )
H2S 0.006
NH3 0.05
CI2 0.01
Requirements on Electrostatic Discharge Prevention
Although many antistatic considerations have been given to MSR 20, damage to the router’s circuit or
even the whole equipment may still happen when the static electricity exceeds the tolerance threshold.
In the communication network to which the routers are connected, static induction mainly comes from two
aspects: external electric fields such as outdoor high voltage power line or thunder and internal
environment like flooring materials or the whole equipment structure. Thus, the following should be
considered to safeguard the equipment against ESD.
• Make sure that the equipment and the floor are well grounded.
• The equipment room is dust-proof.
• Maintain an appropriate humidity and temperature.
• Wear an ESD-preventive wrist strap and uniform when contacting the circuit board.
• Place the uninstalled circuit board on the antistatic workbench, with its face upward, or put it into
the static shielding bag.
• When observing or removing the uninstalled circuit board, please touch the edge of the circuit
board, and avoid contacting the devices on it.
Requirements on Electromagnetic Environments
The interference sources, no matter where they come from, affect the routers with capacitance coupling,
inductance coupling, radiation of electromagnetic wave, common impedance (including the grounding
system) or conducting line (power line, signal line and transmission line etc.). So the following should be
considered:
• Take effective measures to prevent the power system from being interfered with by the power grid
system.
• Use an earthing system or lightning protection grounding different from that for the power supply
equipment and keep them as far as possible.
• Keep the router far away from the radio launcher, radar launcher, and high-frequency devices
working in high current.
• Use electromagnetic shielding when necessary.
Requirements on Preventing Lightning
Although many measures have been taken to protect MSR 20 from lightning, if the lightning intensity
exceeds a certain range, damage to the router may still happen. To protect the router from lightning
better, the following should be considered:
• Ensure the PGND wire of the chassis is well grounded.
• Ensure the ground point of the socket of AC power supply is well grounded.