Solar Lattice

Measurement

Zero inverter AC output

ID
meas:zero-ac-output
IRI
https://solarlattice.org/kb/meas/zero-ac-output
Status
active

The inverter stops feeding power into the grid, so the AC output power reading drops to zero. With the ON/OFF switch set to OFF, the display's Pac value should read 0.0. An inverter in a failure state produces no power. A complete inverter failure, where the unit is not operating, is a listed failure mode for this component. When the inverter detects a DC arc fault while running, it disconnects from the AC grid. It stays off until someone clears the arc fault or resets the operation inhibition by hand. Pressing the emergency stop button trips the DC load switches and the AC circuit breakers right away, which disconnects the inverter from the grid. An internal inverter fault can also cause an emergency stop status. On some hybrid units, the rapid shutdown or emergency power off switch stops all AC output, to both the grid and the backup loads. If the DC input does not supply enough power, for example because of snow on the modules or low irradiation, the inverter stops feeding in and cannot reconnect to the grid. If no power is fed into the grid for more than 10 minutes, some inverters disconnect, shut down and turn their LEDs off. The communication interfaces stay powered. Before working on the unit, confirm that no voltage is present. Use a measuring device rated for the inverter's maximum AC and DC voltage.

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Signals

Monitoring channels where this signature appears, named by SunSpec model point.

PointUnitPattern
model_103.WWAC power stays at zero
model_103.WHW-HRenergy counter stops increasing
model_302.POAIW-PER-M2normal plane-of-array irradiance while the inverter output is zero
model_103.AAAC current stays at zero during the event
model_103.DCAADC input current falls to zero because power conversion stops

Referenced by

Data