What is Arc fault?

Answer: A high power electrical discharge between two or more conductors is known as an arc fault. Heat from this discharge has the potential to disintegrate the insulation on the wire and start an electrical fire. Arc faults vary greatly in intensity and length, with currents ranging from a few amps to thousands of amps.

What type of arc fault?

Answer: 

There are three common types of DC arc faults. explain below with example.

Series – A series arc occurs when a connection is broken while the PV is producing current. Any intermittent connection in the DC circuit has the potential for producing a DC arc fault. These connections may include soldered joints within the module, compression type wire connections, connectors used on the wire leads attached to PV modules, connections in DC isolators, connections in the inverter, any DC circuitry in the inverter or any of the DC cabling in the string circuit.

Parallel – Parallel arcs occur when there is a breakdown in the insulation system and current flows between positive and negative. Two conductors of opposite polarity in the same DC circuit are often run in close proximity to each other. The insulation between the two wires can become ineffective due to animals chewing on them, UV breakdown, embrittlement, cracking, moisture ingress and mechanical damage. Parallel arc faults can continue along the conductors towards the array burning materials along the way.

To ground – This fault only requires the failure of one insulation system to ground. This can be the solar module frame, the solar array racking, the roof or any other grounded surfaces.