Solar Lattice

Symptom

Power optimizer not reporting

ID
symptom:optimizer-not-reporting
IRI
https://solarlattice.org/kb/symptom/optimizer-not-reporting
Status
active
Also known as
No Communication with Power Optimizer, No String Communication, non reporting optimizer, string down

The monitoring platform raises this alert, not the inverter, when it gets no communication from one power optimizer or from a whole string of them. On the inverter, the status screen shows fewer reporting optimizers than installed ones in the P_OK count, and the LCD can identify which optimizers are missing. If only one or two scattered optimizers have no production while the rest produce, likely causes are the connections, the module or a power optimizer failure. Lift the panel, check the connections and measure the DC voltage of the optimizer and the module. Before sending anyone to site, check the logical layout in the portal. The optimizer may already have been replaced without its serial number being updated, or it may never have been assigned to a string. If a whole string is down, a wiring fault is more likely than the optimizer. Measure the string DC voltage at ground level, then start the roof inspection at the junction boxes and connectors. A string voltage of 0V points to a disconnected optimizer output. A voltage above zero but below the optimizer count points to an optimizer missing from the string, a module not connected to its optimizer, or reversed polarity. To find a faulty optimizer, disconnect the string and measure each optimizer output. The one without a 1V safety voltage is the suspect, and its connections, polarity and module should be checked. Remote pairing may bring the optimizers back, but a wiring fault that changes resistance can take the string down again, so bring a spare optimizer to site.

<!-- review notes

Claims

observed_as

c1 drafted · lead Zero power with irradiance

Typical non-reporting case: a monitoring alert plus no production from one or two non-contiguous optimizers while the other optimizers keep producing.

c2 verified · fact Low reporting optimizer count proposed

The inverter status screen shows P_OK xxx/yyy where the first number is smaller than the second. The missing optimizers can be identified on the LCD.

verified by: review-workflowverified on: 2026-10-24

c3 drafted · lead Zero DC voltage reading

A string voltage of 0V points to a disconnected power optimizer output.

review note: support check: partial - Passages say 0V string voltage means optimizer output disconnected, but do not link it to a non-reporting optimizer or to the specific signal.; review: partial - The tables say a 0V string voltage means an optimizer output is disconnected, but they never connect that to an optimizer not reporting, which is the symptom claimed.

c4 drafted · lead String voltage below optimizer count proposed

String voltage is above 0V but lower than the number of optimizers. Possible causes are an optimizer not connected in the string, a module not connected to an optimizer input, or reversed string polarity.

c5 drafted · lead Optimizer safety voltage missing proposed

With the string wires disconnected, a faulty optimizer is the one whose output does not show the 1V safety voltage.

review note: support check: partial - The passage describes finding the optimizer lacking 1V safety voltage with wires disconnected, but frames it as a malfunction under high string voltage, not as a non-reporting observation.

Referenced by

Data