Orange introduces a 5A switch with surge arrester and 2 weeks ago I bought one to test (Normal - 480/= and Squire 500/=). So I remove it parts and check how they setup for the surge protections. Here I put all the images accordingly and I hope it’ll help full to you to when you’re planning to buy such item.
Only problem is I couldn’t tell this circuit is working perfectly. Because normally people using some different circuits other than this and those circuits are always connecting to Earth line. But in this system, they never try to connect it with the Earth line.
Here is the diagram for the circuit they usedMOV = Metal oxide varistor
GD = Gas Discharge