What is Injection Testing?
Otherwise known as “witness testing”, a secondary protection injection test is the connection of an injection test unit to a PV solar system. The connection induces a current overflow, resulting in the protection relay to trip and cutting the current of electricity back into the grid. This is done under numerous scenarios in order to test and see if the circuit breakers work efficiently during different tolerances of stimulated current. Injection tests are mandatory to all PV solar systems 30kVA and greater, according to the Standards Australia. Complying with AS/NZS 4777:2015, requiring inverters of 30kVA and greater systems to have secondary protection devices to act as safeguards to ensure excess current is not fed back into the grid. This is part of the Distributor Network Application process, completion and approval of the PV solar system is necessary otherwise connections to the grid will be denied.