What this MCCB delivers — and where the ratings matter
The Siemens 3VA2225-7KP32-0AE0 is a SENTRON 3VA2 molded case circuit breaker rated for 250 A continuous current (Iu) in a 3-pole configuration, fitted with the ETU850 electronic trip unit. This is a line-protection device — not a motor-protective breaker — so it is sized for feeder and distribution duty where selectivity and fault coordination drive the spec. The ETU850 brings communication capability, meaning it can report trip events and load data over the integrated bus interface, which matters if you are building a panel that needs energy monitoring or remote diagnostics without an add-on module. Breaking capacity is the headline: 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 6.3 kA at 690 V. That 330 kA figure at 240 V is exceptionally high — it tells you this breaker is designed for high-fault installations like transformer secondaries or large busway feeds where upstream SCCR demands a robust interrupting rating. At 690 V the capacity drops to 6.3 kA, so verify the available fault current if you are applying it on a 690 V system. Thermal derating is published across the operating range: the breaker carries 250 A continuously at ambient temperatures up to 50 °C, 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 your panel ambient runs above 50 °C — common in sealed enclosures or near heat sources — factor that derating into your load schedule rather than relying on the 250 A nameplate.
Panel fit and integration notes
Dimensions: 105 mm wide, 181 mm high, 86 mm deep. The 105 mm width is the standard 3-pole MCCB footprint for the 3VA2 frame size — it fits existing SENTRON mounting bases and busbar systems without adapter plates. IP40 on the front face means it is protected against tools and small wires entering the front, but not against water ingress; mount it inside a rated enclosure for washdown or outdoor environments. The breaker ships with 4 auxiliary switches (HQ type) pre-installed. That gives you two normally-open and two normally-closed contacts for status feedback to a PLC or indication lamp without buying add-on blocks. No undervoltage release or shunt trip is fitted from the factory — those are field-installable accessories if your safety circuit requires a UVR. Maximum power dissipation is 48 W at rated current.
What the ETU850 trip unit enables
The ETU850 is an electronic trip unit with communication function. Rated insulation voltage is 800 V, and the breaker is rated for use on systems up to 690 V (with the derated breaking capacity noted above). The operating temperature range is -25 °C to 70 °C, with storage from -40 °C to 80 °C — suitable for unheated warehouses or outdoor enclosures as long as the IP40 front is protected.