Based on Schneider documentations and according to NFC15 100 regulation it's mandatory to install the Surge Protection Device after main breaker and in parallel of the installation.(catalog page attached)
But in some case it's allowed to install type 1 before the main breaker.(type 1 only)
So,regarding type 1 surge arresters,normally they should be connected after the main breaker and in parallel of the installation,otherwise,the client should provide the following configuration details to study the possibility:
1-Earthing system
2-Network voltage and poles (complete electrical diagram)
3-Isc level
4-Kind of SPD type 1 or 2
5-Local specific regulation requirements
6-Kind of loads
While types 2 or 3 and normally it is connected after the main breaker.
But in some case it's allowed to install type 1 before the main breaker.(type 1 only)
So,regarding type 1 surge arresters,normally they should be connected after the main breaker and in parallel of the installation,otherwise,the client should provide the following configuration details to study the possibility:
1-Earthing system
2-Network voltage and poles (complete electrical diagram)
3-Isc level
4-Kind of SPD type 1 or 2
5-Local specific regulation requirements
6-Kind of loads
While types 2 or 3 and normally it is connected after the main breaker.