Operation manual ISOTEST 4 S / 4 S
p l u s
Page 19
3. Indirect grounding through the soil
Indirect grounding is used where the distance between the test object and
a suitable grounding terminal is greater than 15 m. Typical examples are
completely muffled pipelines.
Required accessories:
Trailing ground wire
Part number 0174120000
Grounding stick with cable, 2 m
Part number 0174200000
Application:
1. Connect the plug of the trailing ground wire to the grounding jack of
the ISOTEST
®
test equipment.
Spread the bronze spiral of the trailing ground wire (6.5 m) on the soil
in full length.
2. Connect the clamping tongs at the cable from the grounding stick to a
non-insulated area of the test object.
3.
Deeply bury the grounding stick in the soil. If the soil is dry,
thoroughly water the respective area to obtain a low-resistance
connection.
4.
Turn the ISOTEST
®
test equipment on and perform the high-voltage
test.
Indirect grounding can only be used if the following conditions are met:
the test object is grounded
because of its characteristics, the soil exhibits the required
conductivity
-
all types of moist soil are suitable
-
unsuitable are, e.g., dry sand, asphalt, and flags.
4. Capacitive grounding
Capacitive grounding is used where direct or indirect grounding is not
possible.
This is the case when the test object has metal carrier material that is
inaccessible or consists of completely coated material.
