mapj1:
(For example This dataasheet from Megger suggests an accuracy on lop tests of 5% of reading +/- 5 counts in the least significant digit.
So if the reading on the display was 0.080 then the real value to generate that could lie anywhere between 0.071 to 0.089 (5% is 4 in the last place plus another 5 counts)
This is odd! Would that be the case with an analogue meter?
The Megger MFT's minimum value for EFLI is 0.01Ω so if the reading is anything up to 0.06Ω, it could be zero. Or you go to a TT installation where the EFLI is 100Ω and it could be anywhere between 90Ω and 110Ω. It's that last digit which troubles me. If the machine has measured to an accuracy of +/- 5% (much worse than a simple ruler!) why can it not express the value accurately?
why can it not express the value accurately
This is odd! Would that be the case with an analogue meter?
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