The location: EU, industrial yard, pump station for crude oil... Ex zone
Surge protection device for control cabinet in industrial yard?
The application: control cabinet (installed outside EX zone) for heating cables for heating tanks of instrum. air:
Control cabinet data: 230V AC, TN-S, main cable max 4mm2, main CB C20A/1p/10kA
The question: Which SPD and a corresponding fuse should I install in a cabinet?
The fuse specially troubles me, since it seems ridiculous for instance to have a SPD fuse of 125A gG/gL (often recommended) and a main MCB of C20A (which is perfectly suitable for the application).
Sometimes it seems that I don't see the wood out of trees...
If you need any additional info, just write...
Thanks a lot