Spurious fault event

A spurious fault event is a fault or error message that appears even though no real hardware fault exists. The device may still block operation, as if the fault were real. One documented case is a firmware defect in an EV charger: an earlier firmware version reported a relay error and put the unit into operation inhibition while the relay hardware was fine. The manufacturer corrected this in a later firmware release. Before replacing parts, check the installed firmware version and update it, either automatically or by hand. Monitoring software can also raise false alarms. A statistical detector that compares measured power and voltage with predicted bounds flagged a fault when voltage briefly went above the upper bound right after a shading test had ended. Such detectors are tuned for a low false alarm rate, but some false alarms still occur. Check whether the flagged deviation lines up with a real, lasting change in output before sending a crew.

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• sentence 3: support check: partial - The fix in FW 2.01.39.R and checking/updating (automatic or manual) are stated, but 'before replacing parts' is not stated.
• sentence 5: support check: partial - The passage supports low false alarm targets (<10%, lowest 7%) and some false alarms, but the advice to check for a real, lasting change before dispatching a crew is not stated.
• sentence 4: review: partial - The passage confirms that LAPART flagged a false fault when voltage went above the upper bound at 14:45 after the module was no longer shaded, but it does not call LAPART a statistical detector or say the excursion was brief. -->