Siemens Power DistributionSiemens Power Distribution

5SY, 5SP Miniature Circuit Breakers


Leitungsschutzschalter - Miniature Circuit Breakers  5SP 5SY


MCBs are used to protect plants in buildings and for industrial applications. The devices can be used as main switches for the disconnection or isolation of plants.

For industrial applications and in plant engineering, miniature circuit breakers can be supplemented with additional components, such as auxiliary switches, fault signal contacts, shunt trips, undervoltage releases, remote controlled mechanisms and RC units.

The devices are approved for worldwide use according to IEC standards for systems up to 250/440 V AC. 60 V DC per pole is permitted in DC systems.

For North America, we also have additional certification to UL 1077 for use as "supplementary protectors" in systems up to 480Y/277 V AC. For use in ship building, the devices have numerous certifications according to shipping classifications BV, DNV, GL and LRS. For further information, please refer to the section "Configuration".


  • The infeed can be either from the top or the bottom as the terminals are identical.

  • Clear and visible conductor connection in front of the busbars that can be easily checked.

  • Large and easily accessible wiring space enables easy insertion of conductor in the terminal.

  • Integrated movable terminal covers located at the cable entries ensure the terminals are fully insulated when the screws are tightened.

  • The effective touch protection when grasping the device considerably exceeds the requirements of VBG 4/BGV A3.

  • Manual snap-on fixing and release systems that require no tools enable fast assembly and disassembly of MCBs.

  • Highlighted labeling field on all modular installation devices for uniform, quick and simple labeling.

  • The MCBs can be quickly and easily removed from the busbar assembly by hand, e.g. if connections need to be changed.

  • Time saving if parts need to be replaced because the busbars no longer need to be freed from the adjacent devices.