Connecting up 
  6.1 Lightning protection, power supply and grounding 
SCALANCE W788-x / W748-1 
Operating Instructions, 06/2016, A5E03678333-10 
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Danger to life from overvoltage, fire hazard 
When using outdoor antennas, the shared or even grounded pin of the circuit must be 
connected to the shield of the coaxial cable and with all touchable conductive parts and 
circuits. Otherwise, in the event of a fault there may be illegally high voltages on touchable 
parts. 
Damage to the device due to potential differences 
To fully eliminate the influence of electromagnetic interference, the device must be 
grounded. There must be no potential difference between the following parts, otherwise the 
device or other connected device could be severely damaged: 
•  Housing of the SCALANCE W700 and the ground potential of the antenna. 
•  Housing of the SCALANCE W700 and the ground potential of a device connected over 
Ethernet. 
•  Housing of the SCALANCE W700 and the shield contact of the connected Ethernet 
cable. 
Connect both grounds to the same foundation earth or use an equipotential bonding cable. 
Do not connect or disconnect cables to or from the device when a flammable or 
combustible atmosphere is present. 
Replacing components may impair suitability for Class 1, Division 2 or Zone 2. 
Do not open the device when the supply voltage is turned on.