SIRIUS 3RV2021-4EA40 Motor Protection Circuit Breaker — 32 A, Class 10, 25 kA
The Siemens SIRIUS 3RV2021-4EA40 is a motor protection circuit breaker designed for the 32 A range, carrying a Class 10 trip characteristic that matches standard motor start profiles — it holds through the inrush without nuisance tripping, then clears a locked-rotor fault fast enough to protect the winding insulation. Rated 32 A at 480 V and 32 A at 600 V, with a breaking capacity of 25 kA at 400 V AC. At 240 V AC the interrupting rating reaches 100 kA, giving plenty of headroom for high-fault panels downstream of a large transformer. Built-in phase failure detection means the breaker trips on loss of one phase — a common failure mode that single-element overload relays can miss, and one that causes single-phasing damage on delta-connected motors.
Mounting and Panel Integration
Clearance requirements: 50 mm above and below, 30 mm to the side, zero forward or backward — tight enough for dense MCC rows.