Mini Circuit Breaker ABB SH203-B16A 3P 16A B Characteristic 6 kA

ABB SH203-B16A is a three-pole mini circuit breaker with a B tripping characteristic and a rated current of 16 A. Intended for residential and light commercial electrical installations, it provides protection against overloads and short circuits while allowing compact DIN-rail mounting in distribution boards. The device has a breaking capacity of 6 kA and a toggle actuator for manual switching and visual status indication.

Advantages

The SH203-B16A combines compact dimensions with reliable thermal-magnetic tripping, delivering predictable performance for circuits with predominantly resistive loads. Its B characteristic ensures fast disconnection of low-magnitude short-circuits and overloads typical in lighting and socket circuits. The unit’s DIN-rail compatibility and three-pole design simplify installation and reduce panel space compared with separate single-pole devices.

Suitable for

• Residential distribution boards for protecting lighting and socket circuits
• Small commercial premises with three-phase circuits of up to 16 A per pole
• Protection of motors and appliances with mainly resistive loads where a B characteristic is appropriate

When it may not be suitable

This breaker may not be appropriate for circuits requiring higher breaking capacity than 6 kA or where C or D tripping characteristics are needed to tolerate higher inrush currents (for example, certain large motors or heavy inductive loads). It is also unsuitable for applications demanding selective coordination with upstream or downstream devices specified at different time-current curves without a system study.

Key specifications

• Poles: 3-pole
• Rated current: 16 A
• Tripping characteristic: B (thermal-magnetic)
• Breaking capacity: 6 kA
• Mounting: DIN-rail
• Function: Overload and short-circuit protection

How to use

Mount the breaker on a standard DIN-rail inside the distribution board and connect line and load conductors to the corresponding terminals according to the panel wiring diagram. Ensure correct tightening torque of terminal screws and that the device is installed in a de-energised state. After wiring, switch the toggle to the ON position and verify circuit continuity and correct operation with appropriate test equipment. Regular visual inspection and periodic testing help maintain protection reliability.

What to consider before purchase

• Confirm that 16 A rated current and B characteristic match the load type and expected inrush currents
• Verify that a 6 kA breaking capacity is sufficient for the installation’s prospective short-circuit levels
• Ensure three-pole protection is required for the intended three-phase circuit
• Check available panel space and DIN-rail compatibility

Usage recommendations

Use the ABB SH203-B16A in circuits with predominantly resistive or low-inrush loads such as lighting and general-purpose outlets, and coordinate with upstream protective devices when system selectivity is required. Follow local electrical codes and have installation and testing performed by a qualified electrician.