If you are searching for the RCBO BS number, the answer most commonly required in UK and IEC-based electrical procurement is BS EN 61009-1. This is the principal product standard associated with residual current circuit breakers with overcurrent protection used in residential, commercial, and similar installations.
However, merely the BS number is not sufficient as a basis for approval or procurement decisions. Engineers, distribution cabinet manufacturers, and the procurement team must also evaluate the rated current, residual operating current, breaking capacity, equipment type, and relevant conformity certificates. Referencing standards is only one aspect of ensuring overall compliance.
This guide explains the meaning of the BS standard number for RCBO and its connection with the IEC and EN systems. It also introduces how to interpret the markings on actual equipment and clarifies how to verify in actual purchasing scenarios whether the products comply with the standards.
The RCBO BS number most commonly referenced in UK projects is:
BS EN 61009-1 BS EN 61009-1
An RCBO (Residual Current Breaker with Overcurrent protection) combines two protective functions in a single device:
The “BS EN” prefix indicates British adoption of a European Norm, while “61009” identifies the product family for RCBOs. The “-1” part typically refers to general requirements for devices of this category.
In terms of procurement, this number helps identify the product standard series, but it does not guarantee its applicability to all installation scenarios. The buyer is still required to confirm:
For practical RCBO selection guidance, related product information can be found here: RCBO
The BS EN 61009-1 standard specifies the general performance and safety requirements for RCBOs (Residual Current Operating Circuit Breakers with Overcurrent Protection) used in domestic and similar fixed installations.
In practical engineering terms, it typically covers:
This standard does not specify specific installation rules, but rather ensures that the RCBO exhibits predictable characteristics under the specified test conditions.
This ensures that the equipment is not only correctly identified, but also has the necessary, verifiable documentation that meets the project requirements.
The RCBO standard exists in multiple adoption layers:
These standards are structurally consistent, but their prefixes indicate the jurisdictional area over which the standards have been adopted and promulgated.
In procurement practice, this matters because:
A common verification mistake is assuming equivalence guarantees approval. In reality, engineers must compare:
In procurement, it is often encountered that the rated current (for example, 40A) and the remaining working current (for example, 30mA) are confused. It should be noted that these two values represent completely different protection functions and must not be confused.
In addition, the product labels must be checked against the manufacturer’s technical parameter table and the conformity declaration. Just having printed marks is not sufficient to pass the project approval.
Even though the functions are similar, the product standards followed by different protective equipment are still different.
| Device | Main Function | Common Standard |
| RCBO | Overcurrent + residual current protection | BS EN 61009-1 |
| RCCB | Residual current only | BS EN 61008-1 |
| MCB | Overcurrent protection only | BS EN 60898-1 |
| AFDD | Arc fault detection | BS EN 62606 |
The modular protection device may involve multiple functional requirements, but this does not replace the necessity of conducting system-level coordination analysis during actual installation.
The basic standard BS EN 61009-1 remains the reference for most types of RCBO, but depending on the design type, additional requirements may apply.
For the smooth DC residual current, type B equipment may introduce additional performance considerations. In certain cases, depending on the design scope, reference standards such as BS EN 62423 may also be applicable.
Pole configuration does not change the core product standard. However, electrical system compatibility and switching arrangement must still be verified.
Bidirectional suitability is not guaranteed by the BS number alone. Line/load directionality, internal design, and manufacturer instructions must be checked.
When arc fault detection is integrated, the device may need to comply with both RCBO and AFDD-related standards. Always confirm the declared conformity scope for the exact model.
Before approving an RCBO for procurement or installation, a structured verification process is recommended.
Compliance should always be tied to the exact model, not a generic product family description.
In the UK, project specifications commonly reference BS EN standards, meaning BS EN 61009-1 is the expected baseline for RCBOs.
In other IEC-aligned regions:
Importantly, compliance is not automatically transferable between regions. A device accepted in one market may still require additional certification evidence in another.
In practical procurement workflows, buyers often need more than a standard reference. They may require:
The coordination between engineers and suppliers in the early stage helps to reduce specification errors and ensures that the selected RCBO complies with the electrical and technical documentation requirements.
The actual selection requires comprehensive consideration of the equipment’s rated parameters, verified supporting documents, system failure levels, and the specific requirements of the project. Before making the final purchasing decision, engineers must ensure that the specific model’s compliance proof is confirmed.
When referring to RCBOs (Residual Current Breakers with Overcurrent Protection), the most commonly cited BS standard number is BS EN 61009-1; this standard sets out the general requirements for such breakers in electrical installations in the UK and those based on IEC standards.
Yes, most standard RCBOs used in residential and similar applications are designed and tested according to BS EN 61009-1. However, buyers must confirm the exact model’s compliance documentation.
IEC 61009-1 is the international base standard, while BS EN 61009-1 is its British adoption. The technical requirements are aligned, but the prefix reflects regional publication and adoption.
BS EN 61008-1 applies to RCCBs (residual current devices without overcurrent protection), not RCBOs.
In some cases, Type B functionality may require additional standards depending on design and manufacturer declaration. Always verify the datasheet for the exact compliance scope.
The buyer should cross-check the model, data sheet, test report and certification documents to ensure that they comply with the requirements of the BS EN 61009-1 standard and the project specifications.
