Motor Protection Circuit Breaker for 400 V Panels
It is rated for Trip Class 20, meaning it allows a 20-second overload duration at locked-rotor current before tripping — standard for general-purpose conveyors, pumps, and fans that don't need the fast trip of Class 10 or the extended ramp of Class 30.
At 400 V, the 3RV2031-4PB15 delivers 30 kA breaking capacity, which is the common requirement for IEC motor control centers backed by a 400 V transformer. The interrupting rating at 500 V is 5 kA, and at 690 V it is 2 kA, which limits application on 690 V systems to low-fault-current scenarios.
Dimensions are 55 mm wide, 140 mm high, and 149 mm deep — the 55 mm width is a single modular unit, so it occupies one 55 mm slot on the DIN rail. Main contact terminals accept M6 bolts, and the conductor cross-section ranges from 2x 0.5 mm² up to 2x 2.5 mm² solid or stranded.
Switching Frequency and Auxiliary Ratings
Maximum switching frequency under AC-3 and AC-3e duty is 15 operations per hour — adequate for motor start-stop cycles in material handling and conveyor applications, but not for high-speed jogging or reversing. Auxiliary contact ratings: 1 A at 24 V, 0.15 A at 60 V, 0.5 A at 230 V. At 110 V, 125 V, and 220 V the rated current is 0 A, meaning no auxiliary contact is available at those voltages — verify the control voltage before specifying.