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2CSR256140R1205 ABB DS203NCB20A30 DS203NC B20 A30 20 A 30 mA Type A RCBO 3P+N
ABB DS203NCB20A30 is a 20 A B-curve 3P+N Type A RCBO with 30 mA residual-current sensitivity and 6 kA short-circuit capacity for three-phase circuit protection.
£164.87
Why Choose the ABB DS203NCB20A30 RCBO?
The ABB DS203NCB20A30 (DS203NC B20 A30) is a compact and reliable residual current circuit breaker with overcurrent protection (RCBO) designed to protect three-phase electrical circuits against overloads, short circuits and earth leakage faults. As part of the ABB System pro M compact DS203NC series, it combines residual-current and overcurrent protection in a single four-module device for commercial and industrial electrical installations.
This Type A RCBO detects sinusoidal AC residual currents as well as pulsating DC residual currents, providing effective protection for modern electrical loads. Its 30 mA rated residual current provides additional protection against electric shock, while the integrated B tripping characteristic provides sensitive overcurrent protection for circuits with relatively low inrush currents.
With a rated current of 20 A, a 3P+N configuration and a rated voltage of 400–415 V AC, the DS203NCB20A30 is designed for three-phase circuits requiring combined overcurrent and residual-current protection. Its compact four-module DIN-rail format helps conserve distribution-board space while providing comprehensive circuit protection in one device.
Key Advantages
- Combined residual-current and overcurrent protection in one compact RCBO.
- 20 A rated current with B tripping characteristic.
- 30 mA residual operating current for additional protection against electric shock.
- Type A residual-current detection for sinusoidal AC and pulsating DC residual currents.
- 3P+N configuration designed for three-phase circuits with neutral.
- Compact four-module DIN-rail design for space-efficient distribution-board installation.
Key Features
- ABB System pro M compact DS203NC series.
- 20 A rated current.
- B tripping characteristic.
- 30 mA rated residual current.
- Type A residual-current protection.
- 3P+N configuration with four poles and three protected poles.
- 6 kA rated short-circuit capacity (Icn).
- Protection against overload, short circuit and residual earth leakage currents.
- DIN-rail mounting for straightforward integration into electrical distribution systems.
Reliable Protection for Three-Phase Electrical Circuits
RCBOs such as the ABB DS203NC combine the functions of a miniature circuit breaker and residual-current device in one unit. This enables a single protective device to respond to overloads, short circuits and potentially hazardous earth leakage currents while simplifying distribution-board design and reducing the space required for circuit protection.
The DS203NC Type A range is designed for commercial and industrial installations where protection against sinusoidal AC and pulsating DC residual currents is required. The B characteristic provides responsive protection for circuits with relatively low inrush currents, while the 30 mA residual-current sensitivity provides additional protection against electric shock.
Typical Applications
- Three-phase commercial electrical circuits.
- Industrial distribution boards and control panels.
- Three-phase final circuits requiring 30 mA residual-current protection.
- Building services and electrical distribution systems.
- Lighting and general-purpose electrical loads.
- Circuits requiring combined overload, short-circuit and earth-leakage protection.
Technical Specifications
| Series | System pro M compact DS203NC |
|---|---|
| SKU | DS203NCB20A30 |
| ABB order code | 2CSR256140R1205 |
| Product type | Residual current circuit breaker with overcurrent protection (RCBO) |
| Number of poles | 4 |
| Protected poles | 3 |
| Pole configuration | 3P+N |
| Rated current | 20 A |
| Tripping characteristic | B curve |
| Rated residual current | 30 mA |
| Residual-current type | Type A |
| Rated voltage | 400–415 V AC |
| Rated insulation voltage (Ui) | 500 V |
| Rated impulse withstand voltage (Uimp) | 4 kV |
| Rated short-circuit capacity (Icn) | 6 kA |
| Frequency | 50 / 60 Hz |
| Energy limiting class | 3 |
| Mounting type | DIN rail |
| Width | 4 modules / 71 mm |
| Dimensions (W × H × D) | approx. 71 × 85 × 69 mm |
| Net weight | approx. 0.48 kg |
| Standards | IEC/EN 61009-1, IEC/EN 61009-2-1 |
Frequently Asked Questions
What is the ABB DS203NCB20A30 used for?
The ABB DS203NCB20A30 is used to protect three-phase circuits with neutral against overloads, short circuits and residual earth leakage currents.
What is the rated current of the DS203NCB20A30?
The RCBO has a rated current of 20 A and uses a B tripping characteristic.
What residual-current sensitivity does this RCBO provide?
The DS203NCB20A30 has a rated residual operating current of 30 mA, providing additional protection against electric shock.
What does Type A mean on this ABB RCBO?
Type A means the RCBO is designed to detect sinusoidal alternating residual currents as well as pulsating DC residual currents.
What is the breaking capacity of the ABB DS203NCB20A30?
The DS203NCB20A30 has a rated short-circuit capacity Icn of 6 kA, providing dependable short-circuit protection for suitable commercial and industrial circuits.
Trusted ABB Circuit Protection
ABB System pro M compact circuit protection devices are designed for dependable electrical distribution in commercial and industrial installations, combining compact construction with coordinated protection against electrical faults.
