A current trace’s sign depends on how the measurement is arranged. A negative waveform is not automatically proof of reverse operation or a failed component.
Preserve the setup information
Keep clamp orientation, channel scale, units and the circuit being observed. Ask the technician whether the reference and zeroing procedure were appropriate. Comparing two captures without their setup details can produce a false difference.
The report should explain what the waveform establishes about the complaint. Do not request a module replacement from a graph whose measurement direction is unknown. A useful capture is one that another technician can interpret with its conditions and method intact, rather than a cropped image showing only a shape.
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