Inverter display check

The inverter display check means reading the fault codes, status messages and live measurements on the inverter LCD or in its menus. It helps you work out why the inverter has stopped or raised an alarm. When the inverter is in fault mode, the screen shows the most recent or current fault. The same codes can often be found in the data log of the monitoring system. An arc detection board failure appears as an arc board error, and the inverter will not reconnect to the grid until the board is working again. A real arc fault shows as a separate alarm that must be cleared by hand from the menu. For a temperature sensor fault, first read the temperature on the display. An implausible value, such as a sensor reading of -25C, points to a poorly connected or damaged sensor. A fan that is not working properly triggers a Fan Fail warning on the LCD. Internal power stage or other internal faults appear as internal fault or protection codes. Display readings of grid voltage, grid frequency and PV voltage should be checked against a meter reading, because the measurement circuit itself may be faulty. The display only points to a likely cause. Before touching the fan or other internal parts, switch off at the LCD, disconnect AC and DC, and wait for the stored energy to discharge.

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• sentence 1: support check: partial - The passages support fault codes and live measurements shown on the display for diagnosing, but 'status messages' and 'menus' as a defined check are only loosely covered.
• sentence 3: support check: partial - The arc board error and not reconnecting until the board is OK are stated, and the arc fault is cleared manually, but 'a separate alarm' is not explicit (the arc fault is shown on the LCD, as 'Arc Fault Detected!' in u11).
• sentence 4: support check: partial - Reading the display first and -25C as a possible cause alongside poor contact or a damaged sensor is stated, but nothing calls -25C an implausible value that points to those causes.
• sentence 6: support check: partial - The passages say to compare the display with measured AC or DC voltage and note a possible bad measurement circuit for some grid voltage cases, but they don't cover frequency or PV voltage across the board as a general rule.
• sentence 7: support check: partial - u21 gives the switch-off, disconnect AC and DC, and wait 15 minutes steps for fan work, but the claim that the display only points to a likely cause isn't stated, and the 'stored energy' wording only appears in u2.
• sentence 1: review: partial - The passages support fault codes, operating-mode screens and live PV/grid measurements on the LCD for diagnosing a non-working inverter, but 'menus' and diagnosing a 'raised alarm' are not stated.
• sentence 4: review: partial - Observing the temperature display first and the poor-contact/damaged-sensor causes are supported, but the passages list a -25C reading as a separate possible cause rather than an implausible value that points to poor contact or damage.
• sentence 7: review: partial - For fan work the passages give switching off at the LCD, disconnecting AC and DC and waiting 15 minutes (and energy discharge appears for a restart), but 'the display only points to a likely cause' and extending this to other… -->