Photovoltaic inverter leakage alarm

Why does a PV inverter fail?

Probable Reason: This fault indicates that the inverter and the leakage current protector have detected leakage current from the PV system to the ground. In such cases, the safety regulations require that the inverter must stop generating and enter the protection mode to protect the safety of people and equipment. Failure Analysis 1.

Can a transformer-less inverter cause DC current leakage to ground?

In photovoltaic systems with a transformer-less inverter, the DC is isolated from ground. Modules with defective module isolation, unshielded wires, defective Power Optimizers, or an inverter internal fault can cause DC current leakage to ground (PE - protective earth). Such a fault is also called an isolation fault.

What causes a I leak in an inverter?

Typically the I leak is a kind of ground fault that occurs when the inverter is in operation and CURRENT is flowing through the inverter circuit ( Parasitic Capacitance ). There are several things that can cause this fault listed below that we have found in the field so far. This is not a comprehensive list but ideas to use when troubleshooting.

How do I troubleshoot a PV system with a ground fault?

Extreme caution must be used when troubleshooting PV systems with ground faults. To comply with NEN-EN-IEC 62446 test the string resistance using the insulation tester at 1000V. Every time the SolarEdge inverter enters operational mode and starts producing power, the resistance between the ground and the DC current-carrying conductors is checked.

How do I know if my inverter has an Isolation Fault?

You can identify an isolation fault using either SetAPP or the inverter LCD display. An isolation fault may disappear and recur after a short period (especially if it is caused by morning moisture), therefore it is recommended to troubleshoot the fault as soon as it occurs before it disappears.

How do you know if a PV panel is leaking?

It is easy to tell from the formula for leakage current (shown above) that the larger the PV panel area (S) , the higher the conductivity (ε) of air , and the shorter the distance (d) between the PV panel and ground or roof , the higher the leakage current will be.