The Siemens 3VA4125-5ED34-0AA0 is a 3-pole SENTRON molded-case circuit breaker rated 25 A at 40 °C, with a TM210 thermal-magnetic release that gives fixed instantaneous trip at 300 A. Breaking capacity hits 85 kA at 240 V and 35 kA at 480 V — enough headroom for most 480 V panelboards without cascading upstream. The 75.1 mm depth and 76.2 mm width match the standard 3VA4 footprint, so it drops into existing SENTRON mounting bases and busbar systems without re-drilling the gland plate.
Thermal derating and the TM210 release
At 65 °C it still holds 22 A, and at 70 °C it carries 21 A — so in a warm enclosure you lose about 4 A off the nameplate, not a full de-rate curve step. The TM210 release is fixed thermal-magnetic: the magnetic trip is locked at 300 A (12x In), no adjustment dial. That makes this breaker a straight swap for any panel whose coordination study already assumes a fixed instantaneous at 12x.
Integration into a 5SQ2370 panel
The 3VA4125-5ED34-0AA0 shares the same 3-pole 25 A class and similar 76.2 mm width as the 5SQ2370-2YA05 series. Both use a standard SENTRON mounting base, so the breaker swaps into an existing 5SQ2370 panel without rewiring the busbars or re-terminating the load cables. The main difference is the TM210 fixed release on this unit versus the adjustable release on the 5SQ2370 line — verify the coordination study accepts a fixed 12x instantaneous before committing the swap.