It covers a single phase (1P+N) at 230/240 V AC, 50/60 Hz. The 20 kA nominal discharge current per differential mode (L/N) and 40 kA common mode (N/PE) mean it handles direct lightning-induced surges on a service entrance or sub-distribution board, not just switching transients. The 25 kA short-circuit withstand ensures the device clears a fault without rupturing upstream — critical for coordination in a panel where the main breaker is sized above that level.
The Type 2 + 3 classification tells you this arrester handles both main incoming surges (Type 2 at the sub-distribution board) and equipment-level protection (Type 3 close to the load) in one unit — no need for a separate fine-protection stage downstream. The MOV + GDT technology combines a metal-oxide varistor for clamping with a gas discharge tube for follow-current extinction; the GDT handles the 100 A common-mode follow current that would otherwise stress a MOV alone. Response time under 25 ns on L/N and under 100 ns on N/PE means it catches fast-rising transients — the kind that damage switch-mode power supplies and electronics before a slower arrester reacts. Temporary overvoltage (TOV) withstand is a real differentiator: 337 V L/N for 5 seconds before failure, and 442 V L/N for 120 minutes in safe failure mode. That means the arrester survives a neutral shift or back-feed from a generator long enough for protection to clear, rather than venting immediately. The N/PE path handles 1200 V for 200 ms — a direct lightning strike to the PEN conductor. If you are specifying for a site with weak utility regulation or generator backup, this TOV curve is the spec that keeps the arrester from becoming the failure point. The pluggable cartridge lets you replace the MOV/GDT module without rewiring the base — a maintenance spare you can swap in under a minute while the board stays live upstream. Local signalling uses a green flag for operating state and red for fault; remote signalling contacts rated 1 A/250 V AC allow a PLC or building management system to log the failure.
Tested to IEC 61643-11:2011 and BS EN 61643-11:2012+A11:2018. UKCA marked for the UK market.