What the ratings mean for fit
The Siemens 3VA2040-6HL46-0AA0 is a SENTRON molded case circuit breaker (MCCB) with an ETU320 electronic trip unit, rated for a continuous current of 40 A across the full ambient range from 40 °C to 70 °C — no derating required within that span. That 40 A rating is the load-side limit; the breaker frame itself is rated for a maximum of 480 A and a minimum setting of 60 A, so the ETU320 is set at the low end of the frame's capability. The 242 kA interrupting capacity at 240 V and 187 kA at 415 V means this breaker safely clears high-fault currents without cascading upstream — a key figure for selectivity studies in distribution panels where the available fault current is known to exceed 100 kA. The 4-pole design suits three-phase plus neutral applications where the neutral must be switched and protected — typical in North American and European distribution panels feeding mixed single-phase and three-phase loads. The IP40 front protection means the breaker face is protected against solid objects over 1 mm but not against water ingress; it is intended for installation inside a dry enclosure, not in washdown or outdoor environments.
Integration and panel fit
The breaker occupies 140 mm width, 181 mm height, and 86 mm depth. That 86 mm depth is the dimension from the mounting surface to the front of the breaker — critical for enclosure depth planning, especially in retrofit panels where the back panel clearance is tight. The ETU320 trip unit is an electronic overcurrent release with no communication function and no ground-fault monitoring; it provides adjustable long-time, short-time, and instantaneous protection settings via DIP switches or rotary dials on the front face. No undervoltage release and no voltage trigger are fitted, so any undervoltage or shunt-trip function must be added externally if required.