•Faulty cartridges can be replaced without changing the entire SPD.
• Cartridges can be replaced with mains voltage ON.
• All cartridges are marked with characteristics for ease of maintenance.
Dedicated Protection of the Neutral
•The 1P+N and 3P+N SPDs with dedicated protection of the neutral
pole discharge the common and differential mode overvoltages that
may occur in installations with TT and TNS systems, when there is a