Arc Fault Detection

Arc Fault Detection Devices help to reduce the risk of electrical fires

Broken wires, loose connections, crushed cables, worn insulation can all cause hidden arc faults in electrical circuits, which if left undetected, can erupt into flames in just seconds. AFDDs (also known as Arc Fault circuit interrupter in some countries) isolate the faulty circuit the moment an arc fault is detected.

Hidden Danger

An arc fault is not always easy to see, since it can occur in hidden places such as damaged cables, inside walls, a loose connection in a hidden junction box, or socket outlets.

Arc fault fires: how they start

Very localised phenomena can cause an electrical fire. Check out this video to learn more about different type of arc faults and how they start.

How do arc faults occur?

Tight corners

Loose plugs

Fastener damage

Worn insulation

Exposed wires

Pinching

Poor termination

Pests

Crushing

What is an Arc Fault Detection Device?

An AFDD is a circuit breaker that automatically cuts the electricity supply when it detects an arc fault in a circuit. By immediately cutting off the electricity supply, AFDDs help to prevent arc faults from reaching temperatures where fires can break out.

Schneider Electric AFDDs comply with IEC 62606, a new international standard covering product safety and performance.

Acti9 iArc

Arc Fault Detection device only

Acti9 iDPN H VigiArc

Arc Fault detection with circuit breaker and RCCB function

Where to use AFDDs?

Since 2019, AS/NZS 3000:2018 recommends the use of AFDDs to protect against arc faults in final sub circuits in the following applications:

Premises with sleeping accommodation like homes, dormitories, etc.

Premises and locations for children, handicapped or elderly people like day care centres, pre-schools, schools, retirement and nursing homes.

Premises for gathering of people like cinemas, universities, restaurants, underground stations, office complexes, shopping malls.

Locations with irreplaceable goods or historical buildings like Museums, galleries, etc.

Locations with risk of fire due to nature of processed or stored materials like barns, wood working shops.

Locations with combustible construction materials like wooden buildings.

Fire propagating structures.

Escalated Risk

Arc fault risk is expected to be higher for power circuits (connected to socket outlets) due to following reasons:

Arcing in extension boards.
Damage to cables plugged into socket outlets behind furniture like bedsides or sofas.
Damage to extension leads due to bending around corners or trapping under furniture.
Damage to plugged cables due to temperature variation, ultraviolet rays, vibrations, humidity, and rodents in outdoor environment.

Therefore, we highly recommend using AFDD for power circuits as a minimum.

Can other protective devices replace AFDDs?

Thanks to smoke detectors, building occupants get alerted to the presence of smoke AFTER a fire has started. Early detection helps occupants to evacuate before a fire gets too big. Unfortunately, smoke alarm can’t prevent fires. Lower mobility of people due to age, disability, location might not provide enough time to evacuate. AFDDs are designed to help PREVENT an electrical fire due to arc faults from starting.
Compact and easy to install, AFDDs fit into electrical switchboards, alongside other protective equipment. They cannot be replaced by any other protective devices like miniature circuit breakers (MCBs), surge protection devices (SPDs), or residual current devices (RCDs). While these protect against specific electrical hazards, they are not designed to detect arc faults.