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2) After the AC power cord connector of the device is plugged into a multi-purpose socket of the
power lightning arrester (lightning protection busbar), if the green LED is on while the red LED is off,
the lightning protection is functioning normally.
Pay attention when the red LED is on. You should correctly tell whether the grounding cable is not well
connected or the live and zero wires are reversely connected. You can use a multimeter to examine the
polarity of the multi-purpose socket of the power lightning arrester.
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If the live and zero wires are on the right and left respectively, supposing you are facing the socket,
the PE terminal of the power lightning arrester is not grounded.
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If not, the polarity of the power socket is reversed. In this case, open the power socket to correct the
polarity. After that, if the red LED is still on, the PE terminal is not grounded.
Selecting and Installing a Signal Lightning Arrester (Optional)
No signal lightning arresters are shipped with the firewall.
Generally, you need to install a signal lightning arrester between a signal cable and the connected
device, to protect the device against surge over-voltage resulting from lightning strokes and other
interferences.
Because the signal lightning arrester is serially connected to a signal cable, the signal lightning arrester
must satisfy the requirements of network performance indexes such as data transmission bandwidth, as
well as the lightning protection performance requirement. Therefore when selecting a signal lightning
arrester, you need to consider such performance indexes as lightning protection, bandwidth,
transmission loss, and interface type.
The device supports three types of signal lightning arresters:
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Voltage-limiting protection parts–signal lightning arrester–maximum discharge current
2.5KA/protection voltage 25V—SMB-75J/SMB-75J-1W-10Mbps
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Voltage-limiting protection parts–signal lightning arrester–maximum discharge current
2.5KA/protection voltage 25V-BNC-75K/BNC-75K-10Mbps
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Voltage-limiting protection parts–single lightning arrester (U port)-maximum discharge current
3KA/comman mode 400 V/differential mode 170V-RJ11
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The signal lightning arrester should be grounded to a place as near as possible. The grounding
resistance must be less than 4 ohms and must be less than 1 ohm in special cases.
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Connect the grounding cable to the special-purpose grounding cable of the signal lightning arrester
and connect it to the grounding grid, instead of connecting it to the lightning rod or lightning belt.
