2CSR256240R2254 ABB DS203NC C25 A S100 RCBO 3P+N 25 A 100 mA

Why Choose the ABB DS203NC C25 A S100 RCBO?

The ABB DS203NC C25 A S100, order code 2CSR256240R2254, is a compact 3P+N residual current circuit breaker with overcurrent protection (RCBO) designed to protect three-phase circuits against overloads, short circuits and earth fault currents. Part of the ABB DS200 / DSH200 RCBO range, this selective Type A device combines residual current and overcurrent protection in a space-saving four-module format for commercial and industrial electrical installations.

The DS203NC provides protection against sinusoidal alternating and pulsating DC residual currents while incorporating conventional circuit-breaker protection against overload and short-circuit conditions. Its Type A residual current characteristic makes it suitable for modern electrical loads that can generate pulsating DC earth fault currents, while the selective S-type characteristic supports coordinated residual-current protection in installations where selectivity is required.

With a rated current of 25 A, C tripping characteristic, 100 mA rated residual operating current and 6 kA short-circuit breaking capacity, the DS203NC C25 A S100 provides comprehensive circuit protection for three-phase systems with neutral. Its compact 3P+N four-module design helps minimise distribution-board space while providing combined RCBO protection in a single device.

Key Advantages

• Combined residual current, overload and short-circuit protection in one device.
• 25 A rated current with C-curve overcurrent tripping characteristic.
• 100 mA residual current sensitivity for earth fault protection.
• Type A detection for sinusoidal AC and pulsating DC residual currents.
• Selective S-type operation for coordinated residual-current protection.
• 3P+N configuration designed for three-phase circuits with neutral.
• 6 kA breaking capacity according to the DS203NC A S range specification.
• Compact four-module construction saves space within distribution boards.

Key Features

• ABB DS203NC RCBO series.
• 25 A rated current.
• C tripping characteristic.
• 100 mA rated residual current (IΔn).
• Type A residual current protection.
• Selective S-type characteristic.
• 3P+N pole configuration.
• 6 kA rated short-circuit breaking capacity (Icn).
• Test pushbutton for checking correct residual-current protection operation.
• Earth fault indicator assists with identification of residual-current trips.
• Contact position indication provides clear visual indication of contact status.
• Compact four-module DIN rail format for space-efficient switchboard installation.

Combined Protection for Three-Phase Circuits

An RCBO combines the functions of residual-current protection and overcurrent protection within a single device. The ABB DS203NC C25 A S100 therefore protects connected circuits against overload and short-circuit currents while also detecting earth leakage currents that could otherwise create electrical hazards or damage equipment.

The DS203NC range is designed for modern three-phase installations where switchboard space and reliable protection are important. Its compact four-module construction can reduce the space required compared with separate residual-current and miniature circuit-breaker devices, while the earth fault indicator and contact position indicator simplify fault identification and maintenance.

Typical Applications

• Three-phase commercial electrical distribution systems.
• Industrial distribution boards and switchboards.
• Three-phase circuits requiring combined overcurrent and earth fault protection.
• Electrical installations requiring selective residual-current protection.
• Machinery and industrial equipment distribution circuits.
• Commercial and industrial installations where distribution-board space is limited.