SENTRON 3VA2 MCCB — 250 A, 3-pole, ETU350, line protection
The Siemens 3VA2325-6HN32-0KH0 is a SENTRON 3VA2 series molded case circuit breaker (MCCB) rated for 250 A continuous current at 40 °C, with three poles and an ETU350 electronic overcurrent release for line protection duty. Breaking capacity reaches 242 kA at 240 V, 187 kA at 415 V, and 40 kA at 690 V — figures that govern fault-clearing capability at the point of common coupling. The unit ships with a factory-installed shunt trip (STL) and a 2+1 auxiliary contact block (2 auxiliary switches + 1 trip alarm switch HQ).
Breaking capacity and coordination
At 240 V the MCCB interrupts 242 kA; at 415 V and 440 V it holds 187 kA, then drops to 121 kA at 500 V and 40 kA at 690 V. These are the Icu (ultimate breaking capacity) values for the frame — they determine whether the breaker coordinates with downstream devices under fault. The ETU350 release supports adjustable long-time, short-time, and instantaneous pickups, giving the selectivity engineer room to shape the trip curve against branch-circuit breakers or motor starters.
Thermal derating and ambient limits
Rated continuous current Iu is 250 A from 40 °C through 50 °C ambient. At 55 °C it derates to 240 A, at 60 °C to 235 A, at 65 °C to 230 A, and at 70 °C to 225 A. Operating ambient range spans -25 °C to +70 °C; storage range is -40 °C to +80 °C. Maximum power loss is 37.5 W — relevant for enclosure heat budgeting when the breaker is enclosed in a non-ventilated panel.
Accessories and wiring provisions
The breaker includes a shunt trip (STL) for remote tripping and a 2+1 auxiliary contact block (two auxiliary switches plus one trip alarm switch HQ). The supplied basic switch is order code 3VA2325-6HN32-0AA0; the integrated auxiliary trip module is 3VA9688-0BL33. A voltage trigger is present, undervoltage release is not fitted, and there is no communication function or phase-failure detection. The trip indicator is standard. Latching endurance is rated at 15,000 operations. Dimensions: 138 mm wide, 248 mm high, 110 mm deep.