What this MCCB carries — and what the ratings mean for the panel
The Siemens 3VA2225-6JP32-0CA0 is a SENTRON molded case circuit breaker rated for 250 A continuous current, 3-pole, with an ETU550 electronic trip unit configured for line protection. That 250 A holds flat from 40 °C up to 50 °C — no derating needed in a warm enclosure — then steps down to 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C. For a hot-strip mill panel near the furnace rolls, that 200 A floor at 70 °C is the number to size against, not the 250 A nameplate. Breaking capacity is voltage-dependent: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 6 kA at 690 V. On a 480 V distribution bus that 187 kA figure gives substantial SCCR headroom for coordination studies — it interrupts fault currents without cascading upstream. The part includes an undervoltage release (UVR) as the auxiliary release design — that trips the breaker when control voltage drops below a threshold, a common requirement for emergency-stop circuits and safety isolation in drive-fed sections. Communication function is present on this variant, which means it can report status and accept remote commands over the plant network, though the specific protocol is not detailed in this listing. This is a 3-pole device with no auxiliary contact version fitted and no ground-fault monitoring. The integrated auxiliary trip order code for the UVR is 3VA9608-0BB24; the basic switch without the UVR is 3VA2225-6JP32-0AA0.
Physical fit — dimensions and panel integration
Dimensions are 105 mm wide, 181 mm tall, and 86 mm deep. It mounts on a DIN rail or directly to a backplate in a standard MCCB footprint. The 105 mm width for a 3-pole 250 A frame is consistent with SENTRON 3VA2 family panel cutouts — verify the existing busbar spacing if retrofitting into an older panel.
Electrical and environmental limits
Rated insulation voltage Ui is 800 V. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Maximum power loss is 50.5 W — factor that into enclosure thermal calculations if the panel is densely populated. Mechanical endurance is 20,000 operations.