Hi everyone,
I’ve noticed that we consistently apply 4 minutes for the tan delta (TD) test at each voltage step. I was wondering if anyone knows where this 4-minute duration comes from, or if there is a standard, calculation, or reference table that defines it.
It seems to be common practice (and I use it as well), but I’d like to understand the technical or standard-based justification behind it.
Thanks in advance.
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