Power Network Application Trainer
– Earthing / Grounding network impedance measurement
60
Figure 39-2: 2 Clamps measurement
Two current clamps are used: generator and measuring current clamps. The driver
(generator) clamp injects a voltage (current) in the earthing system (loop).
If the total loop earth impedance of the electrodes Z
e1
, Z
e2
and Z
e3
connected in parallel
is much lower than the impedance of tested electrode Z
e4
, then the result can be
considered as ~ Z
e4
. Other individual impedance could be measured on the same
manner.
Notes:
AC test current I
e
is injected through the generator current clamps (fixed or
sweep mode; 82
Hz … 329 Hz)
2.3.2.6 HF-Earth Resistance (25 kHz) measurement
The high frequency measuring method offers the advantage of eliminating the influence
of adjacent tower earthing’s connected by overhead grounding wire (automatic
compensation of inductive components).
Figure 40-2: HF-Earth Resistance (25 kHz) measurement
Summary of Contents for MI 3298
Page 55: ...Power Network Application Trainer Earthing Grounding network impedance measurement 55 ...
Page 56: ...Power Network Application Trainer Earthing Grounding network impedance measurement 56 ...
Page 124: ...Power Network Application Trainer Earthing Grounding network impedance measurement 124 ...
Page 228: ...MI 3290 Earth Analyser 228 ...
Page 229: ...MI 3280 Digital Transformer Analyser 229 ...
Page 230: ...MI 3280 Digital Transformer Analyser 230 ...
Page 231: ...MI 3250 MicroOhm 10A 231 ...
Page 232: ...MI 3205 TeraOhmXA 5kV 232 ...