What is an arc fault?

An arc-fault occurs when loose or corroded connections make intermittent contact and causes sparking or arcing between the connections. This translates into heat, which will break down the insulation of the wire and potentially trigger an electrical fire. Such arcs can range in power and vary a great deal in strength and duration.

What is an AFDD?

Arc Fault Detection Devices use digital electronics to analyse the waveform of an A.C. circuit to detect arc faults. The device continuously monitors the circuit for different variations including the duration of an arc and the waveform. Once the device detects an irregular fault the device trips and disconnects the circuit, reducing the chance of it over heating and potentially causing an electrical fire.
 

Where should AFDDs be used?

AFDDs shall be provided for single-phase AC final circuits supplying socket-outlets with a rated current not exceeding 32A in certain premises. 
For all other premises with socket-outlets up to 32A, the use of AFDDs is also recommended. 

What types of circuits can AFDDs be used on?

The regulations state AC single-phase circuits not exceeding 230V, that includes ring circuits, radials etc. Where used, AFDDs shall be placed at the origin of the circuit to be protected.
 

EKL7-40AFD devices are a single module device which fits the existing busbar system of the existing arrangement. The device offers protection against overcurrent, short circuit, earth leakage and arc fault all in one device and are available in B & C Curve variants. It can direct replacement RCBO in existing consumer units.

Led indicator instruction

Whal to do if AFDD/RCBO trips
1. Disconnect all electrical appliances connected to the circuit, 
2. Reset and trigger AFDD/RCBO to "ON" position; 
3. For the description of LED indicators due to faulty devices-please refer to Table 1 below; 
3.1. If the fault indicator is normal, the tripping fault is a short-circuit or an overload; 
4. Switch AFDD/RCBO to "ON" position and then connect 1 appliance one at a time to the circuit to see which device is causing the tripping of the AFDD; 
5. Once a faulty appliance has been identified, do not use it, until it has been repaired or disconnected from the circuit; 
6. After the faulty appliance has been repaired or disconnected, switch AFDD/RCBO to "ON" position; 
7. If the fault is still not confirmed, please contact a qualified electrician for inspection.

Table 1

The LED light flashing program in Table 1 is described in detail:

1. When the product is in normal operation, the light on the AFDD will remain green; 
2. Should the AFDD trip off and to check for an arc fault trip, put the AFDD into the "ON" position and the red light will flash continuously for 5 cycles. Then the arc module will detect itself and turn green when no fault is detected. If there is a fault, the red light will be lit; 
3. Should the AFDD trip and to check for a Residual current fault, put the AFDD into the "ON" position and the yellow light will keep on for about 2 seconds, and then remain off for about 1 second, for a total of 3 cycles. Then the arc module detects itself and lights green when no fault is detected. If there is a fault, the red light will be on; 
4. Arc self-test failure, red light on (Please contact a qualified electrician as the device may need to be changed.) 

Circuit Diagram

Installation size