3Com 4800G Getting Started Manual page 44

44 C 3: I
HAPTER NSTALLING THE
Connecting the
Grounding Cable
c
S
WITCH
CAUTION: Correctly connecting the grounding cable is crucial to lightning
protection and electromagnetic susceptibility (EMS).
The power input end of the switch is equipped with a noise filter, whose central
ground is directly connected to the chassis, forming the chassis ground (also
known as PGND). This chassis ground must be securely connected to the earth
ground so that the faradism and leakage electricity can be safely discharged to the
ground, enhancing the EMS capability of the switch. Ground your switch as
follows:
When a grounding strip is available at the installation site, attach one end of
■
the yellow-green grounding cable of the switch to the grounding terminal on
the grounding strip and fasten the captive nut. Note that the fire main and
lightning rod of a building are not suitable for grounding. The grounding cable
of the switch should be connected to the grounding system in the equipment
room.
Figure 42 Ground the switch through a grounding strip
(1)
(1) AC power socket
(3) Protection grounding cable
When there is no grounding strip but earth is available near the installation
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location and allows a grounding body to be buried, hammer an angle iron/steel
pipe longer than 0.5 m (1.64 ft) into the earth. Weld the yellow-green
grounding cable of the switch onto the angle iron/steel pipe, and treat the joint
for corrosion protection.
(2)
(3)
(4)
(2) Grounding terminal
(4) Grounding strip