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en:surge_protection [2026/08/06 17:06] – angelegt fasteineren:surge_protection [2026/08/06 17:19] (current) – verschoben fasteiner
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-====== Surge Protection ====== 
  
-A receiver mounted outdoors (balcony, railing, mast) is usually powered via PoE, which means an Ethernet cable runs from outside straight to a switch or router indoors. Thunderstorms in the area can induce voltage spikes on such outdoor cable runs, damaging the connected network equipment. An Ethernet surge protector (surge arrester / voltage limiter) diverts these spikes to earth before they reach the devices inside. 
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-**In short:** one surge protector per outdoor cable run, installed inline into the LAN cable **before the switch**, and it **must be grounded** – without grounding the device does nothing. 
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-===== When do you need it? ===== 
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-  * Receiver outdoors, switch/router indoors → plan for a surge protector. 
-  * Fully indoor installation (e.g. receiver on the windowsill behind glass): not needed. 
-  * A surge protector guards against **induced** surges (nearby lightning, static build-up). It does not protect against a direct strike – that would require a proper lightning protection concept from a professional. 
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-===== What is at risk? ===== 
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-A surge induced on the outdoor cable travels down the line and can destroy whatever is connected to it. There is no guarantee the receiver itself survives – but at ~€20 it is cheap to replace, and the same goes for a PoE injector (~€20). The main financial risk sits at the indoor end of the cable: **a PoE switch (€100 and up) feeding an unprotected outdoor run can get fried**, and in the worst case the damage does not stop there – other devices on the network can be hit as well. 
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-===== Device ===== 
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-A proven option is the **Ubiquiti ETH-SP-G2** (Ethernet Surge Protector, approx. €13): 
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-^ Property ^ ETH-SP-G2 ^ 
-| Connection | 2× RJ45, installed inline into the LAN cable | 
-| PoE | passed through – 802.3af power for the receiver keeps working | 
-| Data rate | Gigabit-capable (the receiver only uses 100 Mbit anyway) | 
-| Mounting | weatherproof, suitable for outdoor installation | 
-| Grounding | screw terminal – **grounding wire is not included** | 
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-===== Installation ===== 
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-  * **Position:** inline in the outdoor run, **before the switch** – i.e. at the indoor end of the cable, as close as possible to where it enters the building. With several outdoor runs, each run gets its own surge protector. 
-  * **Grounding (mandatory):** connect the grounding terminal with **≥ 4 mm² copper wire** (green/yellow) to protective earth / equipotential bonding (PE). **Without grounding the surge protector is useless**, because the diverted surge has nowhere to go. The wire has to be bought separately. 
-  * **Outdoor connectors:** keep them protected (outdoor box / covered), cable entries facing down, add drip loops – then connectors outside are uncritical. 
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-===== See also ===== 
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-  * [[en:faq]] – PoE vs. USB power, jumper settings 
-  * [[hardware_setups]] (German) – PoE variants (802.3af / passive) 
-  * [[externe_antenne]] (German) – outdoor mounting with an external antenna 
en/surge_protection.1786028800.txt.gz · Last modified: by fasteiner