Hi Uwe,
It is usually recommended to avoid harmonics of the power line frequency.
This avoids mains earth-return currents affecting the reading.
Also a 4 probe method, with two outer probes delivering current, and inner
ones measuring voltage in the so called "Wenner" configuration is usually
used.
However I got similar readings to you - around 10 ohms - with moist, garden
soil.
I found the most repeatable readings were when one current and one voltage
probe, 1m apart, were seperated by 10s of meters from the other pair - as is
used for archeological ground resistance surveys.
73
Hugh M0WYE
----- Original Message -----
From: "Uwe Wensauer" <[email protected]>
To: <[email protected]>
Sent: Monday, November 14, 2005 4:31 PM
Subject: LF: How measuring Ground conductivity ?
To discuss
Measure ground conductivity.
I placed two stainless- steel rods ( 3mm dia ) whithin a distance of 7
Meters apart abt 80cm deep into soil
Powered with 50 Hz.
In series with the electrodes is a 10 Ohm resistor. In order to measuring
current, I measure the voltage drop across resistor.
Depending on weather I got 8 Ohm / m = 125mS
Is this measurement setup ( proceeding ) correct ?
Please correct me.
Uwe, DK1KQ
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