The 187 kA interrupting rating at 240 V is the headline number, but note it drops to 121 kA at 415 V and 75.6 kA at 440 V; at 500 V or 690 V it's still 17 kA. That means this breaker handles high-fault utility feeds at low voltage but is still usable on 480 V systems with moderate available fault current. No trip indicator or voltage trigger on this variant, so don't plan on local fault annunciation from the breaker face.
The 3VA1125-5EF32-0BC0 measures 130 mm high, 76.2 mm wide, and 70 mm deep. That 3-inch width (76.2 mm) is the standard 3-pole MCCB footprint — it fits the same DIN-rail or screw-mount slots as other SENTRON 3VA1 breakers. If you're swapping out a competitor's 3-pole MCCB, check the mounting hole pattern; Siemens uses a 90 mm center-to-center on the base, which is common but not universal.