An I leak is a current leakage to ground. This can happen on the AC or DC side of the inverter circuit.

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. 

  1. The DC + or - input of a DC string is swapped with another string in a different position, or a different inverter. If the string is crossed with another inverter strange things can happen, and I-leak is probable. Also you may only have one inverter that runs. If its swapped at the same inverter, you may see under production, and odd behavior from the inverter. This may also be at an RSD level.
  2. Minor ground faults are also a cause of Ileaks, especially if the wire insulation is not broken but reduced in the case of abrasion, or some other action that may cause the insulation to be less in a critical point. Water in conduit or in junction boxes can also cause Ileaks. This can include High humidity depending on the conditions. 
  3. Running long wires to your array or to your transformer/Disconnect can cause an I-Leakage if your wires are undersized.  Be sure to do the appropriate analysis of your wire current capacity for the distance it's running. This may also indicate an issue with the transformer itself.
  4. Low quality AC conductors can cause this issue if the wire is not in good shape from the wire pull or has damaged installation in multiple locations. 

Below is the meaning of each alarm code (pro1-pro4) This indicates how much current is leaking from the system.