The A9L16445: It clips onto a DIN rail, occupying 6 modules of 9 mm pitch (54 mm total width), with a depth of 69 mm and height of 81 mm. That's a standard panel footprint — no surprises for a retrofit into an existing Acti9 distribution board. The headline numbers: 40 kA maximum discharge current (common mode, L/PE), 15 kA nominal discharge current per mode, and a total discharge capacity of 120 kA across all paths. The voltage protection level (Up) is clamped below 1.4 kV at Type 2 duty — that's the let-through voltage your downstream equipment sees during a surge event.
Terminals are tunnel type, accepting 2.5 to 35 mm² on both the line and load side. Tightening torque is 2.5 N·m — standard for this conductor range. The unit ships with a white (RAL 9003) housing, which is the usual finish for Acti9 modular devices. It requires an associated external circuit breaker: Schneider specifies the iC60N, iC60H, or iC60L, all 40 A curve C, with interrupting capacities of 10 kA, 15 kA, or 25 kA respectively. That breaker is your overcurrent backup; the arrester itself handles the surge path. Remote signalling is built in — a single changeover contact (1 C/O) rated 0.25 A / 250 V AC, 50/60 Hz.
Operating temperature range is -25 to 60 °C, storage from -40 to 85 °C, with relative humidity 5 to 90 %. Maximum operating altitude is 2000 m. IK03 impact resistance per IEC 62262.