Accurate earth loop impedance testers or MF tester recommendations for industrial type installations/supplies

Can anyone in the industrial world provide some recommendations for earth loop testers or multi function for accurately measuring very low impedances, close to transformer's or for utilising on circuits with MCCB's. I do not feel my older Megger 1741+ is particularly accurate. When I compare readings to a colleagues modern Metrel touch screen style multifunction tester the impedance readings he obtains are significantly lower. Thanks in advance Colin.

  • I do not feel my older Megger 1741+ is particularly accurate. When I compare readings to a colleagues modern Metrel touch screen style multifunction tester the impedance readings he obtains are significantly lower.

    It does not answer the question, but I assume that both of you have a regular (annual) calibration check. Megger claims an accuracy of ± 5% to the nearest 10 mΩ.

    Why do you feel that your MFT is less accurate than your chum's Metrel?