TP-Link Jetstream Series User manual

Lightning Protection Guide
Rack-mountable Devices
1910012320 REV1.0.1
December 2017

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make any derivative such as translation, transformation, or adaptation without permission
from TP-Link Technologies Co., Ltd. Copyright © 2017 TP-Link Technologies Co., Ltd. All
rights reserved.
http://www.tp-link.com
Intended Readers
This guide is intended for network engineers and network administrators.
Conventions
When using this guide, please notice that the figures are used for demonstration only.
The symbol stands for Note. Notes contains suggestions or references that helps you
make better use of your device.
The information in this document is subject to change without notice. Every effort has
been made in the preparation of this document to ensure accuracy of the contents, but
all statements, information, and recommendations in this document do not constitute
the warranty of any kind, express or implied. Users must take full responsibility for their
application of any products.

Lightning Protection
1
This guide applies to TP-Link rack-mountable devices. To identify if your device is rack-
mountable or not, check the IG (Installation Guide) of the device. The IG of rack-mountable
device contains the content of “Rack Installation“.
You can find the IG from the package of the device or download it from the download center
of our website http://www.tp-link.com/en/download-center.html.
1 Cabling Reasonably
In the actual network environment, you may need cable outdoors and indoors, and the
requirements for cabling outdoors and indoors are different. A reasonable cabling system
can decrease the damage of induced lightning to devices.
Note:
It's not recommended using Ethernet cables outdoors. When cabling outdoors, please use a signal lightning
arrester.
Requirements for Cabling Outdoors
Aerial cabling without safeguard is not allowed.
It’s not allowed cabling down the building to connect network devices in different floors.
Outdoor cables should be buried and paved to the indoor through basement. A piece of
steel wire should be paved underground along the pipe and connected to the lightning
protection terminal of the building for shielding. Before connecting the cable to the
device, install a signal lightning arrester on the corresponding port.
When an aerial cable is set up, the cable should be through a metal pipe (15m long
at least) before coming into the building. The two ends of this metal pipe should be
grounded. Before connecting the cable to the device, install a signal lightning arrester on
the corresponding port.

2
Lightning Protection
It’s not necessary to pave STP cables through pipes. The shielded layer of STP cable
should be well grounded. Before connecting the cable to the device, install a signal
lightning arrester on the corresponding port.
Requirements for Cabling Indoors
When cabling indoors, keep a certain distance away from the devices that may cause high-
frequency interferences, such as down-conductor cable, powerline, power transformer and
electromotor.
The main cable should be paved in the metal raceway of the access shaft. When cabling,
keep the loop area formed by the cable itself as small as possible.
Requirements for the distance between Ethernet cable and other pipelines are shown in
the table.
Other Pipelines
Ethernet Cable
Min Parallel Net Length L (mm) Min Parallel-overlapping Net
Height H (mm)
Down-conductor 1000 300
PE 50 20
Service pipe 150 20
Compressed air pipe 150 20
Thermal pipe (not wrapped) 500 500
Thermal pipe (wrapped) 300 300
Gas pipe 300 20
The two diagrams below demonstrate parallel net length and parallel-overlapping net
height.
Note:
The above minimum net length/height is required when metal raceway is not used. If any requirements
cannot be met, you can add a steel tube or metal raceway for shielding.
Requirements for the distance between Ethernet cable and high-power electric devices
are in following tables.
Cable Pave Way Min Parallel Length
(mm)
<2kVA powerline
Parallel cabling 130
One is in the grounded metal raceway or metal pipe 70
The both are in the grounded metal raceway or metal
pipe 10

Lightning Protection
3
Cable Pave Way Min Parallel Length
(mm)
2 to 5kVA powerline
Parallel cabling 300
One is in the grounded metal raceway or metal pipe 150
The both are in the grounded metal raceway or metal
pipe 80
>5kVA powerline
Parallel cabling 600
One is in the grounded metal raceway or metal pipe 300
The both are in the grounded metal raceway or metal
pipe 150
Device Min Distance
(m)
Switch case 1.00
Transformer room 2.00
Elevator tower 2.00
Air-conditioner room 2.00
2 Connect to Ground
Connecting the device to ground is to quickly release the lightning over-voltage and over-
current of the device, which is also a necessary measure to protect the body from electric
shock.
In different environments, the device may be grounded differently. The following will instruct
you to connect the device to the ground in two ways, connecting to the ground via the power
supply or connecting to the ground via the grounding terminal. Please connect the device to
ground in the optimum way according to your specific operation environment.
Note:
For the device without grounding terminal, please refer to the first way Connecting to the Ground via the
Power Supply only.
Connecting to the Ground via the Power Supply
If the device is installed in the normal environment, the device can be grounded via the PE
(Protecting Earth) cable of the AC power supply as shown in the following figure.

4
Lightning Protection
Figure 1 Connecting to the Ground via Power Supply
Device (Rear Panel) AC Power Cord (with PE cable)
Note:
• The figure is to illustrate the application and principle. The power plug you get from the package and
the socket in your situation will comply with the regulation in your country, so they may differ from
the figure above.
• If you intend to connect the device to the ground via the PE (Protecting Earth) cable of AC power
cord, please make sure the PE (Protecting Earth) cable in the electrical outlet is well grounded in
advance.
Connecting to the Ground via the Grounding Terminal
Use the grounding bar
If the device is installed in the Equipment Room, where a grounding bar is available, you are
recommended to connect the device to the grounding bar as shown in the following figure.
Figure 2 Connecting to the Grounding Bar
Device (Rear Panel)
Ground Cable
Grounding Terminal
Grounding Bar
Note:
The grounding bar and the ground cable are not provided with our product. If needed, please self purchase
them.

Lightning Protection
5
Equipotential Bonding
Equipotential Bonding is the practice of intentionally electrically connecting all earthed
systems to the same grounding grid or connecting the grounding grids of all the earthed
systems together through the ground or overground metal so as to create an earthed
equipotential zone. When lightning occurs, the high voltage produced by lightning current in
all systems will meanwhile exist in their ground cables, and thus all ground cables have the
same electrical potential and basically eliminate the electric strikes between the systems.
The figure below illustrates how to practice equipotential bonding in a network.
Figure 3 Equipotential Bonding
Grounding Terminal Equipotential Bonding Cable
Grounding Bar
Ground Cable
When equipotential bonding, please use a 10 AWG or larger ground cable. The shorter cable
the better, and use a grounding bar to establish an equipotential bonding point.
Note:
The equipotential bonding cable and ground cable are not provided with our product. If needed, please self
purchase it.
Use Lightning Arrester
Power lightning arrester and signal lightning arrester are used for lighting protection.
Power lightning arrester is used for limiting the voltage surge due to a lightning. If an outdoor
AC power cord should be directly connected to the device, please use a power lightning
arrester.
Note:
Power lightning arrester is not provided with our product. If needed, please self purchase it.

6
Lightning Protection
Signal lightning arrester is used to protect RJ45 ports of the device from lightning. When
cabling outdoors, please install a signal lightning arrester before connecting the cable to the
device.
When purchasing or using a signal lightning arrester, please observe the following rules:
»The port rate of the signal lightning arrester should match the rate of the desired port
on the device. If it is not matched, this signal lighting arrester will not work. Purchase a
standard lightning arrester.
»Install signal lightning arrester near the protected device and connect it to the ground via
a shorter ground cable.
Figure 4 Use Lightning Arrester
Ethernet CableEquipotential Bonding CableGrounding Terminal
Signal Lightning Arrester Device
Note:
Signal lightning arrester is not provided with our product. If needed, please self purchase it.