MEPworx Wiring – AFDD categories upgraded

By David Wren

As in Regulation 421.1.7, Arc Fault Detection Devices (AFDDs) now have a higher profile for a greater range of applications. They are also available as different types.

• AFDD - for arc fault detection only.
• AFDD combined with an MCB - arc fault detection plus overload/short circuit protection.
• AFDD combined with an RCBO - arc fault detection with overload/short circuit protection, plus earth leakage protection.

All these AFDD variants have uses in different locations of the distribution, which can be dependent on other localised protective devices.

When setting up a new entry for an AFFD in the Circuit Protective Device (CPD) program, you now have the options to set the AFFD as any of the three available types:

• AFDD
• AFDD/MCB
• AFDD/RCBO

Please note, when setting up the RCD for an AFDD/RCBO, you have the standard selection options for the RCD Trip Unit Type & Range.

In most cases this will typically be a Type A 30mA but please check and confirm in the manufacturer’s data.

Please refer to the Wiring Program's Help (F1) for more information.