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Altai Technologies Ltd. All rights reserved
AX500 Series Installation Manual
To protect other LAN devices inside an equipment room or a rack, we recommend you install one more
surge protector at the entry point to the building. Doing this can discharge the electrical surge into the
ground before it entering the building to cause damages to the equipment.
12.3
Other Deployment Tips for Surge Protection and Site Grounding Practices
Here are some more tips to improve the effectiveness of your surge protection system for fighting against
lightning and power surges:
1.
Don’t directly bond Telecom Earth to Lightning Grounding System. There are many possible and
unpredictable paths for surge current flow down to the Earth as long as it follows the path from high
potential to low potential. A separate earth down conductor for the Lightning Spike and for the telecom
equipment should be used.
2.
Lay the earth wire of lightning ground on one side of the pole and run telecom earth & Ethernet wires on
another side; Separation by the pole body can help minimize the electromagnetic induction between
the two when they are running in parallel along the pole. Or even better, run the Ethernet cable inside
of the mounting pole if possible. The mounting pole will act as insulation and help passing surges to
ground.
3.
Increased separation of lightning grounding spike earth connection and telecom earth connection.
Connect the lightning grounding spike earth with 2m or more separation away from the telecom earth
connection point.
4.
Avoid sharp bends and loops in earth wires. Sharp bends (less than 8” radius) and loops/coils in the earth
wires act as inductors and impede current flow. Use smooth bends when necessary.
5.
Keep Ethernet cable run as straight as possible.
6.
Ensure that the impedance of the equipment earthling network to ground is less than 5 ohms.
7.
Ensure all interconnection points are well bonded, protected against corrosion and are low impedance.
As a common practice, test the conductivity of the grounding system to ensure the installation is solid
and electrically capable of grounding any ambient surge or static.
Note:
Inferior surge protector might increase the overall impedance of the entire Ethernet data
path between the switch and the AP unit. The effective cable distance will suffer for this case, i.e.
< 100 meters. You may need to assemble the same setup in the lab or office to ensure 1Gbps of
connectivity before taking them all out for installation.
