Siemens SENTRON 5SY4 Miniature Circuit Breaker, 3-Pole, 40A, Type C, 400V ac AC, 60 V dc DC, 10 kA Breaking Capacity

This miniature circuit breaker is a three-pole protective device designed for DIN-rail distribution systems in industrial and infrastructure environments. It operates on AC supplies up to 400 V and on DC supplies up to 60 V, providing overcurrent and short-circuit interruption with a Type C tripping characteristic. The unit is intended for installation where IP20 touch protection and combined top/bottom terminals are required, and it meets relevant IEC/EN and UL standards for low-voltage switching devices.

• 10 kA breaking capacity delivers defined fault interruption performance
• Type C characteristic protects moderate inrush loads and circuits
• 3-pole construction enables simultaneous multi-phase disconnection
• Combined terminals permit flexible TOP and bottom conductor connection
• DIN-rail mounting allows straightforward panel integration

• Suitable for three-phase distribution boards in industrial facilities
• Used for motor feeder protection with moderate starting currents
• Ideal for infrastructure electrical panels requiring modular protection
• Can be used for DC control circuits up to 60 V where isolation is needed
• Used with sub-distribution units requiring UL1077 recognition

It typically endures 10,000 operating cycles under mechanical operation.

Solid and stranded conductors from 0.75 mm² up to 35 mm² can be fitted, and finely stranded conductors with ferrules up to 25 mm².

Rated current is 40 A

It conforms to IEC/EN 60898-1 and IEC/EN 60947-2 and holds UL1077 recognition.

Terminals require 2.5 N·m to 3.5 N·m torque, equivalent to 22 lbf·in to 31 lbf·in.