Arc fault detection devices ‘AFDDs’ are a type of electrical safety device that can help to prevent fires. They work by detecting arc faults, which are small electrical sparks that can occur in faulty or damaged electrical equipment or installations. These arc faults can cause fires if they are not detected and extinguished quickly.
Regulation 421.1.7 (BS7671:2018+A2:2022) states that AFDDs complying with BS EN 62606 shall be installed in single-phase AC circuits supplying socket-outlets with a rated current not exceeding 32 A in certain high-risk locations. These locations include:
- High risk residential buildings ‘1.8 m high or greater than 6 storeys’
- Houses of multiple occupation
- Purpose built student accommodation.
- Care homes
In addition to these high-risk locations, AFDDs may also be considered for use in other single-phase circuits not exceeding 32 A in areas where there is a potential for arc faults, such as domestic installations, commercial kitchens and industrial settings.
AFDDs work by analysing the electrical waveform of a circuit. If an arc fault is detected, the AFDD will automatically shut off power to the circuit, preventing the fire from starting. AFDDs are typically installed in consumer units at the origin of the circuit, along with other electrical safety devices such as circuit breakers and residual current devices ‘RCDs’.
The cost of AFDDs varies depending on the type and rating of the device. However, they are generally considered to be a cost-effective way to prevent fires. The average cost of an AFDD is around £100.00, but this can vary depending on the retailer and the specific model.
If you are considering installing AFDDs in your home or business, it is important to speak to a qualified electrician. They will be able to assess your needs and recommend the best type of AFDD for your installation.
Benefits of Using AFDDs
There are several benefits to using AFDDs in your electrical installation. These include:
- Increased fire safety: AFDDs can help to prevent fires by detecting and extinguishing arc faults before they can cause damage.
- Reduced insurance premiums: Some insurance companies offer discounts on premiums for homes and businesses that have AFDDs installed.
- Peace of mind: Knowing that your electrical installation is protected from arc faults can give you peace of mind.
Drawbacks of AFDDs
- Can be relatively expensive.
- Not always necessary in all electrical installations
- May not be compatible with all electrical appliances.
Conclusion
AFDDs are a valuable addition to any electrical installation. They can help to prevent fires and save lives and should be install in instances covered by Regulation 421.1.7 (BS7671:2018+A2:2022). If you are considering installing AFDDs, be sure to speak to a qualified electrician to get the best advice for your specific needs.