Measurement signal error

A measurement signal error means the inverter could not get a valid internal reading. It shows up as a status or event code on the inverter display or in the event log. On Fronius units, code 458 means the measuring signal could not be detected, and the inverter stops feeding into the grid. Code 459 means the same failure during the insulation test. On SMA units, events marked as measurement errors point to the sensing chain. Examples are an offset on the grid current sensor, an offset or deviation in grid voltage or DC voltage measurement, or a fault in the insulation resistance or temperature sensors. On FIMER inverters, the Alarm LED lights with Error Meas V, F or Ileak. These codes mean two redundant internal circuits disagree on grid voltage, grid frequency or DC leakage current. Use the code text to tell the likely cause apart: a voltage sensor fault, a current sensor fault or a temperature sensor fault inside the inverter. For external analog inputs, a red channel LED means a wire break or a value outside the allowed range, so check the sensor wiring first. Internal measurement errors cannot be checked from outside. Switch the inverter off and on again, and if the error comes back, contact the manufacturer's service.

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• sentence 1: support check: partial - Codes shown as status or event messages are supported, but the claim that the inverter 'could not get a valid internal reading' is a generalisation the passages don't state as such.
• sentence 5: support check: partial - The code texts do name voltage sensor, current sensor and temperature sensor faults, but the passages don't state that the text can be used to tell the likely cause apart.
• sentence 6: support check: partial - The red LED meaning is stated, but the advice to check sensor wiring first is not in the passage.
• sentence 1: review: partial - The passages show these errors as status or event codes, but nothing says they mean the inverter could not get a valid internal reading; that wording is a generalisation. -->