What the ratings mean for fit
The Siemens 3VA2225-6JQ32-0BH0 is a SENTRON molded case circuit breaker (MCCB) sized for 250 A rated continuous current (Iu) in a 3-pole configuration, designed for line protection duty. The ETU560 electronic trip unit provides adjustable overload and short-circuit protection curves. Breaking capacity is the headline figure here: 242 kA at 240 V AC, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 6 kA at 690 V. These are not theoretical maximums — they are the interrupting ratings the breaker can clear without welding or rupturing. For a 415 V distribution board, 187 kA SCCR means this breaker handles high-fault scenarios typical of large transformer-fed switchgear. The 6 kA at 690 V is a steep drop-off, so verify the available fault current at that voltage level before specifying. Thermal derating is documented per the evidence: the breaker carries a full 250 A from 40 °C through 50 °C ambient, then derates to 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C. If the panel ambient runs above 50 °C, the continuous current must be adjusted accordingly. The operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Maximum power loss is 50.5 W, which factors into enclosure thermal calculations.
Integration and panel fit
Physical dimensions: 181 mm height, 105 mm width, 86 mm depth. The breaker includes a trip indicator and an undervoltage release. Auxiliary contact configuration is 2 auxiliary switches plus 1 trip alarm switch, HQ type.