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2CSR256140R3085 ABB DS203NCB8A300 RCBO 3P+N B8 Type A 300 mA
ABB DS203NCB8A300 is an 8 A 3P+N B-curve Type A RCBO with 300 mA residual current sensitivity and 6 kA short-circuit capacity for three-phase electrical circuit protection.
£181.35
Why Choose the ABB DS203NCB8A300 RCBO?
The ABB DS203NCB8A300 is a compact and reliable 3P+N residual current circuit breaker with overcurrent protection (RCBO) designed to provide combined protection against overloads, short circuits and earth leakage currents in three-phase electrical installations. As part of the advanced ABB DS203NC series, it combines residual current and overcurrent protection within a four-module device, helping reduce panel space and simplify distribution board design.
This RCBO features a Type B tripping characteristic, an 8 A rated current and Type A residual current protection. Type A detection provides protection against sinusoidal AC residual currents as well as pulsating DC residual currents, making the device suitable for a wide range of modern electrical loads and installations.
With a rated residual operating current of 300 mA, a rated short-circuit capacity of 6 kA and a rated operational voltage of 415 V AC, the DS203NCB8A300 provides dependable circuit and earth-fault protection for three-phase systems. Its DIN-rail format and four-module width make it suitable for distribution boards, control panels and commercial or industrial electrical installations.
Key Advantages
- Combined residual current and overcurrent protection in one compact RCBO.
- 3P+N configuration for three-phase circuits with neutral.
- 8 A rated current with Type B tripping characteristic.
- 300 mA Type A residual current protection.
- 6 kA rated short-circuit capacity.
- Compact four-module DIN-rail design helps optimise distribution board space.
- Protects against overload, short-circuit and residual earth-fault currents.
Key Features
- ABB DS203NC RCBO series.
- 8 A rated current.
- Type B tripping characteristic.
- Type A residual current detection.
- 300 mA rated residual operating current.
- 3P+N, four-pole configuration.
- 415 V AC rated operational voltage.
- 6 kA rated short-circuit capacity.
- 50 / 60 Hz rated frequency.
- DIN-rail mounting for modular electrical distribution systems.
Combined Circuit and Residual Current Protection
RCBOs such as the ABB DS203NC combine the functions of a miniature circuit breaker and residual current protective device in a single unit. This allows one device to protect a circuit against overload and short-circuit conditions while also detecting residual currents caused by insulation faults or current leakage to earth.
The DS203NCB8A300 uses Type A residual current detection and a B-curve overcurrent characteristic. Type A technology detects sinusoidal AC and pulsating DC residual currents, while the B-curve characteristic provides rapid magnetic operation for circuits where high starting currents are not normally expected.
Typical Applications
- Three-phase electrical distribution boards.
- Commercial and industrial electrical installations.
- Machinery and automation control panels.
- Three-phase circuits requiring combined overcurrent and earth-leakage protection.
- Building services and electrical distribution systems.
- Circuits containing electronic equipment capable of producing pulsating DC residual currents.
Technical Specifications
| Series | DS203NC |
|---|---|
| ABB order code | 2CSR256140R3085 |
| EAN | 8012542079422 |
| Product type | Residual current circuit breaker with overcurrent protection (RCBO) |
| Number of poles | 3P+N / 4 poles |
| Protected poles | 3 |
| Rated current | 8 A |
| Tripping characteristic | B curve |
| Residual current type | Type A |
| Rated residual operating current | 300 mA |
| Rated operational voltage | 415 V AC |
| Rated frequency | 50 / 60 Hz |
| Rated short-circuit capacity | 6 kA |
| Ultimate short-circuit breaking capacity | 10 kA |
| Rated conditional short-circuit current | 10 kA |
| Rated insulation voltage | 500 V |
| Rated impulse withstand voltage | 4 kV |
| Protection rating | IP2X |
| Pollution degree | 2 |
| Operating temperature | -25 to +55 °C |
| Mounting type | DIN rail |
| Module width | 4 modules |
| Dimensions (H × W × D) | 85 × 71 × 69 mm |
| Weight | approx. 0.48 kg |
| Standards | IEC 61009-1, IEC 61009-2-1, EN 61009-1, EN 61009-2-1 |
Frequently Asked Questions
What is the ABB DS203NCB8A300 used for?
The ABB DS203NCB8A300 is a 3P+N RCBO used to protect three-phase electrical circuits against overloads, short circuits and residual earth-fault currents.
What is the current rating of the DS203NCB8A300?
The DS203NCB8A300 has a rated current of 8 A and uses a Type B tripping characteristic.
What residual current sensitivity does this RCBO provide?
This model has a rated residual operating current of 300 mA and provides Type A residual current protection.
What is the short-circuit rating of the ABB DS203NCB8A300?
The RCBO has a rated short-circuit capacity of 6 kA, with an ultimate short-circuit breaking capacity of 10 kA.
How many poles does the DS203NCB8A300 have?
The DS203NCB8A300 is a 3P+N four-pole RCBO designed for three-phase circuits with a neutral conductor.
Trusted ABB Circuit Protection
ABB DS203NC residual current circuit breakers with overcurrent protection combine compact modular construction with dependable overload, short-circuit and residual current protection for modern three-phase electrical distribution systems.
