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2CSR256040R3255 ABB DS203NCB25AC300 RCBO 3P+N B25 Type AC 300mA 6kA
ABB DS203NCB25AC300 is a 25 A 3P+N Type B RCBO with 300 mA Type AC residual-current protection, 400–415 V AC operation and a 6 kA rated short-circuit breaking capacity.
£151.14
Why Choose the ABB DS203NCB25AC300 RCBO?
The ABB DS203NCB25AC300 is a compact and reliable 3P+N residual current circuit breaker with overcurrent protection (RCBO) designed to protect three-phase electrical circuits against overloads, short circuits and residual earth-fault currents. As part of the ABB DS203NC RCBO series, it combines residual-current and overcurrent protection within a single four-module device for efficient commercial and industrial electrical distribution installations.
This RCBO has a rated current of 25 A, a Type B tripping characteristic and a rated residual operating current of 300 mA. Its Type AC residual-current characteristic detects sinusoidal alternating residual currents, making the device suitable for appropriate AC circuits where this form of residual-current protection is specified.
With a rated operational voltage of 400–415 V AC and a rated short-circuit breaking capacity of 6 kA, the DS203NC B25 AC300 provides coordinated protection for three-phase plus neutral circuits. Its compact four-module DIN-rail format integrates multiple protection functions into one device, helping conserve valuable space in distribution boards and electrical control panels.
Key Advantages
- Combined residual-current, overload and short-circuit protection in one device.
- 25 A rated current with Type B tripping characteristic.
- 300 mA rated residual operating current.
- Type AC residual-current detection for sinusoidal alternating residual currents.
- 3P+N configuration for three-phase circuits with neutral.
- 6 kA rated short-circuit breaking capacity according to IEC/EN 61009.
Key Features
- ABB DS203NC RCBO series.
- 25 A rated current.
- Type B tripping curve.
- 300 mA residual-current sensitivity.
- Type AC residual-current characteristic.
- 3P+N four-pole configuration with three protected poles.
- 400–415 V AC rated operational voltage.
- 6 kA rated short-circuit breaking capacity.
- 50 / 60 Hz rated frequency.
- Compact four-module DIN-rail design.
Reliable Protection for Three-Phase Circuits
RCBOs such as the ABB DS203NCB25AC300 combine the functions of an overcurrent protective device and a residual-current protective device in a single unit. This enables the device to respond to overload and short-circuit conditions while its residual-current function detects sinusoidal alternating earth-fault currents, providing coordinated protection for suitable three-phase electrical circuits.
The DS203NC series is designed for compact three-phase distribution systems in commercial and industrial applications. Its 3P+N arrangement and four-module construction help conserve panel space compared with separate protective devices, while the Type B overcurrent characteristic provides defined magnetic tripping behaviour for appropriate final circuits.
Typical Applications
- Three-phase electrical distribution circuits.
- Commercial and industrial distribution boards.
- Electrical control panels and switchboards.
- Three-phase circuits requiring 3P+N protection.
- Circuits requiring combined overcurrent and residual-current protection.
- Building services and infrastructure electrical systems.
Technical Specifications
| Series | DS203NC |
|---|---|
| SKU | DS203NCB25AC300 |
| ABB order code | 2CSR256040R3255 |
| Product group | DS200 / DSH200 RCBO |
| Product type | Residual current circuit breaker with overcurrent protection (RCBO) |
| Rated current | 25 A |
| Tripping characteristic | B |
| Rated residual operating current | 300 mA |
| Residual-current type | AC |
| Number of poles | 4 (3P+N) |
| Number of protected poles | 3 |
| Rated operational voltage | 400–415 V AC |
| Rated frequency | 50 / 60 Hz |
| Rated short-circuit breaking capacity (Icn) | 6 kA |
| Short-circuit breaking capacity according to IEC 60947-2 | 10 kA |
| Rated insulation voltage (Ui) | 500 V |
| Rated impulse withstand voltage (Uimp) | 4 kV |
| Energy limiting class | 3 |
| Tripping | Undelayed |
| Overvoltage category | III |
| Pollution degree | 2 |
| Protection rating | IP2X |
| Neutral conductor | Simultaneously switched |
| Maximum connectable conductor cross-section | 25 mm² |
| Operating temperature | -25 to +55 °C |
| Mounting type | DIN rail |
| Width | 4 modules |
| Installation depth | 69 mm |
| Weight | 480 g |
| Standards | IEC 61009-1, IEC 61009-2-1, EN 61009-1, EN 61009-2-1 |
| EAN | 8012542265924 |
Frequently Asked Questions
What is the ABB DS203NCB25AC300 used for?
The ABB DS203NCB25AC300 is an RCBO designed to protect suitable three-phase plus neutral electrical circuits against overloads, short circuits and residual earth-fault currents.
What is the rated current of the DS203NCB25AC300?
The RCBO has a rated current of 25 A and uses a Type B tripping characteristic.
What residual-current sensitivity does this RCBO provide?
The DS203NCB25AC300 has a rated residual operating current of 300 mA and uses a Type AC residual-current characteristic.
What is the breaking capacity of the ABB DS203NCB25AC300?
The device has a rated short-circuit breaking capacity of 6 kA according to IEC/EN 61009.
How many poles does the DS203NCB25AC300 have?
The device has a 3P+N four-pole configuration with three protected phase poles and a simultaneously switched neutral conductor.
Trusted ABB Circuit Protection
ABB DS203NC residual current circuit breakers with overcurrent protection provide compact combined protection for commercial and industrial three-phase electrical distribution systems, integrating overcurrent and residual-current protection in a space-saving four-module design.
