Miniature circuit breakers (MCB) protect electrical systems against overload and short circuits. With tripping characteristics A, B, C or D, they cover all application areas in industry, and residential or nonresidential buildings. The special design of the terminals of Siemens devices also guarantees highly effective touch protection.

Siemens offers a complete range* of miniature circuit breakers from 0.3 to 125 A in all required characteristics A, B, C, and D to cover every application.

• For standard applications: 5SL in 6 kA from 0.3 to 63 A
• For quick installation:
• 5SJ6 …-KS with plug-in terminal up to 6 kA from 10 to 20 A
• For distribution boards with limited installation space: 5SY6 0, 1+N in 1 WE up to 6 kA from 2 to 40 A
• For applications with very high requirements: 5SY to 25 kA from 0.3 to 80 A, 5SP from 80 to 125 A, also for universal current (UC) applications
• For worldwide use, certified to UL 489 and IEC: 5SJ4 …-HG from 0.3 to 63 A

Miniature circuit breakers from Siemens can be used in any desired combination with all kinds of different additional components, for example with auxiliary switches, fault signal contacts, shunt trips, undervoltage releases, remote controlled mechanisms or with RC units for combined personnel and fire protection. These additional components are standard for all Siemens miniature circuit breakers and can be retrofitted whenever required.

The new range of modular circuit breakers provides

• Protection against overloads
• Protection against short circuits
• Suitable for isolation with Positive contact indicator
• Line -load reversibility
• Wide range of accessories eg U/V release, over-voltage release, shunt release, Aux & trip alarm contacts
• More features and more safety to the customers