Hardware Installation and Reference Guide    Appendix C Lightning Protection 
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Appendix C Lightning Protection 
Installing AC Power Arrester (lightning protection cable row) 
The external lightning protection cable row shall be used on the AC power port to prevent the switch 
from being struck by lightning when the AC power cable is introduced from the outdoor and directly 
connected to the power port of the switch. The lightning protection cable row is fixed on the cabinet, 
operating table or the wall in the machine room using the line buttons and screws. 
Figure C-1 Schematic Diagram for the Power Arrester 
 
 
The power arrester is not provided and the user shall purchase it to address the practical 
requirement. Make sure that the PE terminal of the power arrester has been well-grounded; 
 
After connecting the switch AC power plug to the socket of the power arrester (lightning protection 
socket), lightning protection function implements if the RUN LED is Green and the ALARM LED is 
OFF.   
 
If the ALARM LED on the power arrester is Red, you shall check what the reason is, poor 
grounding connection or the reversed connection of the Null and Live lines: Use the multimeter to 
check the polarity of the power socket for the arrester when the LED is Red, if the N line is on the 
left and the L line is on the right, the arrester PE terminal is not grounded; if the L line is on the left 
and the N line is on the right, the polarity of the arrester power cable shall be reversed; if the LED 
is still Red, it is confirmed that the arrester PE terminal has not been grounded. 
Installing the Ethernet Port Arrester