9.1.2 Two-pole earth resistance measurements
Fig 24: Earth 2P start screen
For this type of test, the earth electrode must be disconnected from the installation or equipment it is protecting
but before you do this, see the warning at the start of this section Refer to 9. Earth resistance measurement
on page 37. This test uses one test stake which should ideally be driven into the ground 30 m away from the
electrode under test, which is the maximum distance possible with the test-lead supplied. If necessary, the test stake
can be positioned closer to the electrode under test, but not less than 2 m away from it. The test connections are
made to the electrode under test and to the stake. This method does not deliver the most accurate results, but it is
useful for confirming that the earth electrode is working correctly.
9.2 Hot keys for earth resistance measurement
Hot key 1 Hot key 2 Hot key 3 Hot key 4 Hot key 5
Fig 25: Earth Hot keys
Hot key Function Description
1 Test voltage
Press to change the test voltage from 50 V to 25 V. Press again to change
back. (Not available for stakeless testing)
2 Not used.
3 Help/Save
Before starting a test, press for help on earth resistance measurement.
When the test is complete, press to transfer the results to a connected
Bluetooth
®
device.
4 Not used
5 Test type Currently only allows 2P testing.
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MFT-X1
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Earth resistance measurement
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