VOLTCRAFT ET-02 Bedienungsanleitung Seite 28

Zero balancing/zeroing
The earth meter must be zeroed/zero balanced before any measurement and whenever the measuring
range is changed (20/200/2000 Ohm).
- Attach the measuring leads to the meter in colour order. The green plug into the socket "E" and the
red plug into the socket "C".
- Directly connect the green and red alligator clips to each other. Ensure proper contact between the
two.
- Switch on the meter and select the desired measuring range (20 Ohm for 3-lead measurements, 200
or 2000 Ohm for the simplified measuring mode with 2 leads). The display shows "overload".
- Press the "TEST" button (4). The measurement is started and is signalled by a beep tone and a light-
ning symbol. The displayed resistance value can be set to zero by turning the settings control "0-
ADJ" (2).
- Press the "TEST" button to end the zeroing. The settings control "0-ADJ" may not be adjusted once it
is in the zeroed range for the following earth measurement.
Making earth measurements
- Insert the two metal measurement probes approx. 15cm deep into the ground at 5 to 10 m intervals
from the foundation earthing rod. Do this with the probes in a line as shown in the figure. The ground
must be damp for measurements. If required, pour water onto the ground at the probe sites to ensure
good measurement contact.
- Attach the green measuring lead (5m) to the measuring socket "E" (11) on the meter. The alligator
clamp is then directly connected to the foundation earthing rod for the house/building(s) to be tested.
Ensure proper contact between the two.
- Attach the yellow measuring lead (10m) to the measuring socket "P" (12) on the meter. The alligator
clamp is then directly connected to the first, close probe (p1) of the foundation earthing rod. This con-
nection is also labelled "ES".
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