Surge Protection Neutral with Short Circuit Protection

[Joey_]

For a TN-S earthing system, and surge protector e.g. 3P+N why does the Neutral go through a Circuit Breaker as well? Often shown as a 4P CB with 3P+N SPD.

Thanks.

[Juha]

Hi @Joey_ , do you happen to have a drawing to elaborate your question, please.
I am not sure if you are saying the neutral goes trough the circuit breaker, the residual current device of the surge arr ester.

BR

-juha-