Fluke 1623-2 Manual - Page 31
of all pylon foots are determined, the actual earth resistance R, After values of R
View all Fluke 1623-2 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 31 highlights
Earth/Ground Tester Advanced Operation 4. Read out measured value RE. Note Before setting the earth stakes for probe and auxiliary earth electrode make sure that the probe is set outside the potential gradient of earth electrode and auxiliary earth electrode. Such a condition is normally reached by allowing a distance of >20 m between the earth electrode and the earth stakes as well as to the earth stakes to each other. An accuracy test of the results is made with another measurement after repositioning of auxiliary earth electrode or probe. If the result is the same, the distance is sufficient. If the measured value changes, probe or auxiliary earth electrode must be repositioned until the measured value RE remains constant. Stake wires should not run too close. 5. Apply current transformer to next pylon stub. 6. Repeat measuring sequence. Current feeding point of measuring current (alligator clip) and the polarity of the split core current transformer has to be left unchanged. After values of REi of all pylon foots are determined, the actual earth resistance RE has to be calculated: RE = 1 1 11 1 RE1 + R E2 + RE3 + RE4 Note If the displayed RE value is negative despite correct orientation of the current transformer, a part of the measuring current is flowing upwards into the tower body. The earthing resistance, thus coming into effect, correctly calculates if the individual equivalent resistances (under observation of their polarity) are inserted into the equation above. 23 MyFlukeStore Shop for Fluke products online at: www. .com 1.877.766.5412