Grounding, Power – H3C Technologies H3C S7500E Series Switches User Manual
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EMI
Electromagnetic interference (EMI) might be coupled from the source to the switch through the following
coupling mechanisms:
•
Capacitive coupling
•
Inductive coupling
•
Radiative coupling
•
Common impedance coupling
•
Conductive 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
devices to make sure the EMI levels do not exceed the compliant range.
•
Use electromagnetic shielding, for example, shielded interface cables, when necessary.
•
To prevent signal ports from getting damaged by over-voltage or over-current caused by lightning
strikes, only route interface cables indoors.
Grounding
Using a good grounding system to protect your switch against lightning shocks, interferences, and ESD
is essential to the operating reliability of your switch. Make sure that the resistance between the chassis
and the ground is less than 1 ohm. For more information about the grounding methods of the S7500E
series, see "
Power
Perform the following steps to satisfy the power supply requirements of the S7500E series:
1.
Calculate the total power consumption
The total power consumption of an S7500E series switch depends on card type and quantity and
fan tray power consumption. If the switch provides PoE power, the total power consumption also
depends on PoE power consumption. For more information about the total power consumption of
the S7500E series, see "Appendix A Hardware specifications."
2.
Select power modules according to the total power consumption
To ensure normal operation of the switch, make sure the maximum output power of the power
module that supplies power to the switch is higher than the total power consumption of the switch.
After determining the total power consumption of the switch, you can select appropriate power
modules according to the total power consumption. For more information about the optional
power module models, see "Appendix B Pluggable module ordering guide."
3.
Check that the power supply system on the installation site satisfies the input requirements of the
power modules and parameters such as rated voltage.