PEWA UNITEST TELARIS ERDE Mode D'emploi page 21

auxiliary ground "H" and ground "E". The voltage drop between probe and ground is
measured via probe input "S", and consequently the earth resistance is determined and
displayed.
4 Locate earth rods for auxiliary ground, probe and ground, in one line if possible,
as described in figure 6.2.
4 Distance between probe and
ground, or probe and auxiliary
ground must be at least
20 m. The conductors should
not be parallel to each other
and should not cross to avoid
couplings.
4 Connect test leads to test
instruments and earth
rods/ground.
4 Select "3 pole" measurement
range (13).
4 Set contact voltage (11).
4 Automatic (16) or manual (12) frequency selection and press key "Start"(14).
4 Read measurement result from display.
4 Exchange auxiliary ground "H" and ground "E" by simple exchange of socket plugs.
4 Now press key "Start"(14), read measurement result on display.
4 If the value displayed strongly deviates from the first measured value, proceed
as follows:
4 Relocate the probe approximately
1 ... 2 m towards ground and
then towards auxiliary ground.
If the instrument shows the same
measurement results for
all three measurement layouts,
the probe is located outside the
voltage funnel generated by
ground and auxiliary ground,
within the range of the reference
ground.
4
If the instrument shows a larger
deviation, the probe could be within the voltage funnel of the ground or auxiliary
ground. To avoid this situation, two possibilities are available:
A: Increase distance between ground and auxiliary ground, or
B: Locate the probe (as shown in figure 6.3.1) onto a point of the straight
line, outside the voltage funnel and repeat the measurement.
Also refer to display indications in chapter 7.0
H S E
6.2
6.2.1
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