Hi James,
A lot depends on the overall construction of the diode. The Tracker 2000 has a HIGH range that uses a 60V peak sine wave. If the breakdown voltage of the diode is lower than 60V then you will see a usable signature. If the breakdown voltage is higher then the Tracker will show an open circuit signature. But also keep in mind that many semiconductors have leakage failures which means that they become resistive. In many cases this leakage resistance shows up in the signature regardless of the breakdown voltage.
I hope this helps.
Thanks.
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