SENTRON 3VA2125-6KP46-0AA0 — line-protection MCCB with ETU850 trip unit
The Siemens SENTRON 3VA2125-6KP46-0AA0 is a 4-pole molded case circuit breaker (MCCB) designed for line protection, carrying a continuous current rating of 25 A and fitted with the ETU850 electronic overcurrent release. The ETU850 provides adjustable trip curves and integrated communication and measurement functions, making it suitable for selective coordination in distribution panels where remote monitoring and fault diagnostics are required. The 242 kA breaking capacity at 240 V (187 kA at 415 V) means it can safely interrupt very high fault currents typical of large transformer-fed switchboards without upstream cascading — a critical spec for main or tie-breaker positions in industrial low-voltage distribution.
Breaking capacity and voltage-dependent performance
The interrupting rating drops sharply at higher voltages: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 3.7 kA at 690 V. The 690 V figure is a hard limit — this MCCB is not intended for 690 V main feeders with high available fault current; it fits 400 V-class systems where the full 187 kA rating provides generous headroom for most industrial installations. The 25 A continuous rating is thermally stable across the full operating range (-25 °C to 70 °C), with no derating needed up to 70 °C ambient.
Dimensions: 140 mm wide, 181 mm tall, 86 mm deep. IP40 front protection. Power loss is 0.6 W maximum.