The Schneider Electric A9L16677 is an Acti9 iPRD8r modular surge arrester with a pluggable cartridge, rated as Type 2 + 3 per EN 61643-11 and IEC 61643-11. It protects a 1P+N 230 V AC distribution circuit (TN-S or TT earthing) against both common-mode and differential-mode surges, with a maximum discharge current of 8 kA per mode and a nominal discharge current of 2.5 kA. The MOV + GDT technology handles the energy let-through; the pluggable cartridge means you replace the MOV module without pulling the base from the DIN rail.
The Type 2 + 3 classification is the key fit check: Type 2 (Class II) handles the main distribution-board surge from switching transients and indirect lightning, while Type 3 (Class III) adds a low let-through voltage for sensitive loads downstream. The protection level Up is under 1.4 kV in common and differential modes, which keeps the clamped voltage within the impulse withstand of most downstream equipment. The maximum continuous operating voltage Uc is 340 V L/PE and 260 V N/PE — this sets the upper limit of the nominal 230 V system it can ride through without degrading. The open-circuit voltage Uoc is 10 kV for Type 3 common-mode N/PE and differential-mode L/N, confirming it meets the 1.2/50 µs open-circuit voltage test for sensitive electronics protection.
Clip-on DIN rail mount, 36 mm wide (4 x 9 mm pitches), 81 mm tall, 69 mm deep. Tunnel-type terminals accept 2.5 to 35 mm² on both top and bottom; tighten to 2.5 N·m. The associated circuit breaker is an iC60N/H/L 20 A curve C (Icu 10/15/25 kA depending on variant) — the surge arrester is designed to be paired with one of these for overcurrent backup. The remote signalling contact (1 SD, 1 C/O) rated 0.25 A / 250 V AC lets a PLC or BMS monitor the arrester status without opening the panel.