What this MCCB does and where it lands
The Siemens SENTRON 3VA2025-6JQ42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current Iu of 25 A flat across the full operating temperature range from 40 °C to 70 °C — no derating needed up to the 70 °C ceiling. Its interrupting capacity hits 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 3 kA at 690 V, so it handles high-fault scenarios typical in industrial distribution without cascading upstream. It's equipped with the ETU560 electronic trip unit, which gives adjustable N-conductor protection (OFF, 40 % to 160 % of Iu) and ground-fault monitoring via summation current formation on L + N. The unit communicates — the communication function is built in — so it can talk to a higher-level control system for status and metering without an add-on module. The 86 mm depth, 140 mm width, and 181 mm height fit the standard SENTRON panel footprint. IP40 on the front means it's protected against solid objects over 1 mm but not sealed against moisture — fine for a dry indoor cabinet, not for washdown zones.
Lifecycle and sourcing reality
For a BOM freeze or a new panel design, this part is a safe drop-in today. No LTB clock is ticking. The ETU560 release and communication function mean it's ready for modern switchgear that needs remote monitoring or selective coordination studies.
What the ratings mean for your panel
The 25 A rating is a true thermal-magnetic continuous current — no temperature derating from 40 °C to 70 °C, which simplifies panel thermal calculations. If your cabinet ambient stays under 70 °C, you get the full 25 A per pole. The interrupting capacity at 415 V (187 kA) is typical for a high-fault industrial service entrance or a large sub-distribution board. At 690 V it drops to 3 kA — that's still enough for most motor control center (MCC) applications at that voltage, but verify your available fault current if you're feeding a 690 V drive. Rated insulation voltage Ui is 800 V, so the breaker is insulated for 690 V systems with margin. The IP40 front is standard for a panel-mounted device; the enclosure provides the rest of the ingress protection.
Compliance and documentation
The reference code per IEC 81346-2 is Q, which is the standard designation for switching devices in power circuits. The unit is designed to meet IEC 60947-2 for MCCBs. For specific compliance documents (RoHS, REACH, UL file number), the manufacturer provides declarations on request — the part carries the CE mark and is listed for the European market.