Arc Fault Detection & Protection
RCDs are primarily intended to provide protection against electric shock. However, a fault current may flow through equipment to ground and if this current is above a certain level and is allowed to flow for an excessive period, there may be a risk of electric fire.
The RCD will detect such currents and remove power from the installation if the current is above its rated operating value, and in this regard RCDs can provide protection against electric fires.
RCDs will not provide protection against all types of electrical fault and fire risks. An electrical fire could be caused by arcing between two points and such a fault may not include a residual current, for example series arcing. In such cases an RCD will not provide fire protection. The only effective protection against electrical fires that could be caused by arcing is to use an arc fault protection device. These are referred to as AFCIs in North America, and as AFDDs in most of the rest of the world.
WA provides arc fault protection technology to OEMs worldwide to meet the requirements of AFCIs (UL1699) or AFDDs (IEC62606).