METREL MI 3298, Instruction Manual With Exercises

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Power Network Application Trainer
– Earthing / Grounding network impedance measurement
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Expected result:
Measurement gives the total result, so final calculation is not needed.
Result comparison:
Table 35-2: S-Flex measurement result comparison
S-Flex measurement should be used for pylons, towers, earth resistance
measurements, where condition for each foot could be measured separately.
Measurement method shows direct single foot condition. METREL propose to use four
flex-clamps for detail analyse.
From presented examples we can conclude, that broken foot earthing has no big
influence to total earth resistance but could cause serious problem on the object in case
of fault. Ground wire connection causes that part of current is terminated through the
ground wire and other adjacent towers which influenced to the total result, so for such
object different method should be selects
– HF method. S -Flex method is still useful for
determining of single foot condition.