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2CDA383799R0491 ABB M303P-D12.5 Magnetic Circuit Breaker 25 kA 3P 12.5 A
ABB M303P-D12.5 is a 12.5 A three-pole D-characteristic magnetic-only circuit breaker with 25 kA breaking capacity, designed for reliable short-circuit protection in industrial electrical circuits.
£95.23
Why Choose the ABB M303P-D12.5 Magnetic Circuit Breaker?
The ABB M303P-D12.5 is a high-performance three-pole magnetic-only miniature circuit breaker (MCB) designed to provide reliable short-circuit protection and circuit control in industrial electrical installations. As part of the ABB M300P / S300P circuit breaker range, it is engineered for applications where dedicated magnetic protection is required without thermal overload protection.
This breaker combines a 12.5 A rated current with D-characteristic instantaneous magnetic operation, making it suitable for circuits and equipment where high transient or inrush currents can occur. Its three protected poles allow simultaneous protection and isolation of three-phase circuits, while its modular construction supports straightforward installation within distribution boards and industrial control panels.
With a 25 kA short-circuit breaking capacity at 230/400 V AC and a maximum operating voltage of 440 V AC, the M303P-D12.5 is designed for demanding electrical protection duties. ABB specifies an instantaneous magnetic tripping current of 175 A for this 12.5 A model, providing rapid disconnection under severe overcurrent and short-circuit conditions.
Key Advantages
- Dedicated magnetic-only short-circuit protection for demanding electrical circuits.
- 12.5 A rated current with three protected poles.
- 25 kA breaking capacity at 230/400 V AC for high fault-level installations.
- D-characteristic magnetic operation accommodates circuits with elevated starting and inrush currents.
- 175 A instantaneous magnetic tripping current for rapid fault interruption.
- Compact modular construction simplifies installation in electrical distribution and control equipment.
Key Features
- ABB M300P / S300P magnetic circuit breaker range.
- 12.5 A rated current.
- 3-pole configuration with all three poles protected.
- D tripping characteristic.
- 175 A rated instantaneous tripping current.
- 25 kA short-circuit breaking capacity at 230/400 V AC.
- Maximum operating voltage of 440 V AC, 50/60 Hz.
- IP20 protection rating.
- IEC/EN 60947-2 compliant design.
Reliable Magnetic Protection for Electrical Circuits
Magnetic-only circuit breakers such as the ABB M303P-D12.5 are designed to react rapidly to high fault currents and short circuits. Unlike conventional thermal-magnetic MCBs, their protection function is based on instantaneous magnetic operation, making them particularly useful where overload protection is provided separately or where dedicated short-circuit protection is required.
The ABB M300P range is designed for electrical installations requiring robust magnetic protection and high breaking capacity. The three-pole M303P-D12.5 provides coordinated switching of three-phase conductors and is suitable for industrial, commercial and specialist electrical systems, including critical circuits where dependable short-circuit protection is essential.
Typical Applications
- Three-phase industrial electrical circuits.
- Industrial control panels and distribution boards.
- Motor and machinery circuits with separate overload protection.
- Circuits subject to high starting or inrush currents.
- Industrial and medical IT electrical systems.
- Commercial and industrial power distribution installations.
Technical Specifications
| Series | M300P / S300P |
|---|---|
| ABB order code | 2CDA383799R0491 |
| Product type | Magnetic-only miniature circuit breaker |
| Rated current | 12.5 A |
| Number of poles | 3 |
| Protected poles | 3 |
| Tripping characteristic | D |
| Instantaneous magnetic tripping current | 175 A |
| Short-circuit breaking capacity | 25 kA at 230/400 V AC |
| Maximum operating voltage | 440 V AC |
| Rated frequency | 50/60 Hz |
| Rated insulation voltage (Ui) | 500 V |
| Rated impulse withstand voltage (Uimp) | 6 kV |
| Protection rating | IP20 |
| Pollution degree | 3 |
| Terminal type | Screw terminal |
| Tightening torque | 2.8 N·m |
| Operating temperature | -40 to +70 °C |
| Standards | IEC/EN 60947-2 |
| Dimensions (H × W × D) | 88 × 52.5 × 69 mm |
| Weight | approx. 0.372 kg |
Frequently Asked Questions
What is the ABB M303P-D12.5 used for?
The ABB M303P-D12.5 is a three-pole magnetic-only circuit breaker designed primarily for short-circuit protection and circuit control in industrial and other demanding electrical installations.
What is the rated current of the M303P-D12.5?
The breaker has a rated current of 12.5 A and an instantaneous magnetic tripping current of 175 A.
What is the breaking capacity of this circuit breaker?
The M303P-D12.5 provides a 25 kA short-circuit breaking capacity at 230/400 V AC, making it suitable for installations with high prospective fault currents.
Does the M303P-D12.5 provide thermal overload protection?
No. The M303P-D12.5 is a magnetic-only circuit breaker intended primarily for short-circuit protection. Where overload protection is required, it should be provided by an appropriate separate protective device.
How many poles does the ABB M303P-D12.5 have?
The M303P-D12.5 is a three-pole circuit breaker with all three poles protected, making it suitable for three-phase electrical circuits.
Trusted ABB Circuit Protection
ABB M300P magnetic circuit breakers provide dependable high-performance short-circuit protection for industrial and specialist electrical installations, combining compact modular construction with high breaking capacity and reliable magnetic operation.
