The 5SQ2370-2YA40 is a 3-pole miniature circuit breaker from the SENTRON 5SQ series, rated 40 A at 400 V AC with a C-trip curve.
IP20 finger-safe terminals are standard for enclosed distribution boards. No neutral pole is switched — this is a 3-pole-only device for 3-phase loads where the neutral is not interrupted. The 5SQ design uses the same modular footprint as other SENTRON 5SQ breakers, so swapping between current ratings within the series is a direct rail-clip exchange without rewiring the busbar.
How it compares to lower-current siblings
The 5SQ2370-2YA40 shares the same 3-pole, C-curve, 3 kA breaking capacity, 400 V AC, and 55 mm depth as the 5SQ2370-2YA05 (0.5 A), 5SQ2370-2YA04 (4 A), and 5SQ2370-2YA01 (1 A). The only difference is the 40 A current rating. If your panel was originally specified for a 5SQ2370-2YA05 at 0.5 A, the 40 A version will not drop in without a busbar and conductor re-rating — the physical footprint is identical, but the protection level is completely different. For a like-for-like replacement at the same current, stick to the same rating.