The Niglon MCB6B1-20 20A Type B Miniature Circuit Breaker is a single-pole protective device designed to provide reliable overload and short-circuit protection for suitable domestic and light commercial electrical circuits.
Featuring a 20 Amp current rating, Type B tripping characteristic and 6kA breaking capacity, the MCB6B1-20 is suitable for appropriately designed electrical circuits, including certain radial socket circuits, dedicated appliance supplies and other installations requiring 20A overcurrent protection.
Manufactured in accordance with BS EN 60898-1, this compact circuit breaker features DIN rail mounting, bi-directional operation, a single-module width and screw terminals accepting suitable conductors up to 25mm².
20A Type B Circuit Protection
The Niglon MCB6B1-20 has a rated current of 20A and a Type B tripping characteristic, providing overcurrent protection for suitably designed electrical installations.
Type B miniature circuit breakers are commonly selected for circuits where the connected equipment has relatively low starting currents and does not produce excessive inrush current during normal operation.
The circuit breaker automatically disconnects the supply when an overload or short-circuit fault causes it to trip, helping protect electrical wiring against the effects of excessive current.
Type B Tripping Characteristic
The Type B tripping characteristic provides instantaneous magnetic operation at approximately 3 to 5 times the rated current.
For a 20A Type B MCB, this corresponds to an instantaneous magnetic tripping range of approximately 60A to 100A.
The correct rating and tripping characteristic must be selected according to the connected load, conductor size, circuit design and electrical installation requirements.
6kA Short-Circuit Breaking Capacity
The Niglon MCB6B1-20 has a 6kA (6000A) rated short-circuit breaking capacity in accordance with BS EN 60898-1.
This specifies the breaker's ability to safely interrupt short-circuit faults within its approved operating and test conditions.
The prospective fault current at the installation must be assessed to ensure that the circuit breaker has an appropriate breaking capacity.
Single Pole DIN Rail Mounting
The MCB6B1-20 is a single-pole miniature circuit breaker designed for installation onto a compatible standard DIN rail.
Its compact single-module construction occupies approximately 18mm of DIN rail space, making it suitable for compatible consumer units and electrical distribution equipment.
The front-mounted operating lever allows the circuit to be manually switched on or off and reset following a trip once the cause of the fault has been identified and corrected.
Bi-Directional Operation
Niglon specifies the MCB6B1-20 as bi-directional, allowing current to flow in either direction through the protective device within its approved operating conditions.
This provides additional flexibility for suitable electrical distribution arrangements, subject to the manufacturer's instructions and compatibility with the complete electrical installation.
Bi-directional operation does not remove the requirement to verify the consumer unit, busbar connections and any specific installation restrictions.
25mm² Maximum Cable Capacity
The Niglon MCB6B1-20 features screw terminal connections with a manufacturer-specified maximum cable capacity of 25mm².
The recommended terminal tightening torque is 2.5Nm, helping provide secure electrical connections when installed using suitable conductors and the correct termination method.
The selected conductor size must be appropriate for the circuit design, and all terminations must comply with the manufacturer's installation instructions.
Suitable for Domestic & Light Commercial Circuits
The MCB6B1-20 can provide overcurrent protection for a range of suitably designed electrical circuits.
Typical applications may include:
- 20A radial socket circuits
- Dedicated appliance circuits
- Suitable fixed electrical equipment supplies
- Domestic electrical distribution
- Light commercial distribution circuits
- Compatible consumer units and distribution equipment
The suitability of a 20A Type B MCB depends on the connected load, cable size, installation method, fault conditions and any additional protective requirements.
BS EN 60898-1 Compliant
The Niglon MCB6B1-20 is manufactured in accordance with BS EN 60898-1, the standard covering miniature circuit breakers used for overcurrent protection in household and similar electrical installations.
Niglon lists Semko certification, CE marking and UKCA marking for its Type B miniature circuit breaker range.
The device should be selected and installed by a suitably qualified person within compatible electrical distribution equipment.
Key Features
- Manufacturer: Niglon
- Part Number: MCB6B1-20
- 20 Amp rated current
- Type B tripping characteristic
- 6kA short-circuit breaking capacity
- Single-pole circuit protection
- 230V AC rated voltage
- Bi-directional operation
- Standard DIN rail mounting
- Compact single-module width
- Maximum cable capacity of 25mm²
- 2.5Nm terminal tightening torque
- Overload and short-circuit protection
- BS EN 60898-1 compliant
- Semko certification, CE and UKCA markings
- Suitable for appropriately designed domestic and light commercial circuits
Technical Specifications
| Manufacturer | Niglon |
| Manufacturer Part Number | MCB6B1-20 |
| HEM Model / SKU | NIG20MCB |
| Product Type | Miniature Circuit Breaker (MCB) |
| Rated Current | 20A |
| Tripping Characteristic | Type B |
| Breaking Capacity | 6kA (6000A) |
| Rated Voltage | 230V AC |
| Number of Poles | 1 Pole |
| Bi-Directional | Yes |
| Mounting Type | DIN Rail |
| Module Size | Single Module |
| Nominal Width | 17.8mm |
| Nominal Height | 82mm |
| Maximum Cable Capacity | 25mm² |
| Terminal Tightening Torque | 2.5Nm |
| Standard | BS EN 60898-1 |
| Certification / Marking | Semko, CE, UKCA |
Dimensions are based on Niglon's current range drawing. Installation must follow the manufacturer's instructions and applicable electrical regulations. Consumer unit compatibility should be checked before fitting. This MCB provides overcurrent protection and does not replace an RCD or RCBO where residual-current protection is required.
Why Choose the Niglon MCB6B1-20?
The Niglon MCB6B1-20 20A Type B Miniature Circuit Breaker combines dependable overload and short-circuit protection with compact DIN rail mounting and a straightforward single-pole design.
Its 20A rating and Type B tripping characteristic make it a practical option for correctly designed electrical circuits, while the 6kA breaking capacity and BS EN 60898-1 compliance provide the performance expected from a professional miniature circuit breaker.
With bi-directional operation, 25mm² maximum terminal capacity and 2.5Nm tightening torque, the MCB6B1-20 offers a versatile solution for suitable domestic and light commercial electrical installations.
Any orders below £75 subject to £6.00 carriage
- Stock: 11
- Model: NIG20MCB
- SKU: NIG20MCB
- MPN: MCB6B 120
