ABEM Terrameter SAS 1000 / SAS 4000
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To accept, press the
(or select the <START>
option). This start the electrode test (if you have
selected "Electrode test: Yes" above) or the
measuring procedure (if you have selected
"Electrode test: No"). It is recommended that you
use the electrode test function. When the test is
finished, a list of the electrodes with bad ground
contact is given. You then have the option to skip
a particular electrode, or to improve the
grounding. It may be necessary to connect several
electrodes to each take-out to get sufficient contact
Ch P1 P2 Resistance S.Dev Stacks.
1: .
2: N/A .
3: N/A .
4: N/A .
N=0 I=Auto .
Resistivity: Wenner-a, Section .
LR00004.S4K C1= , C2= .
NOTE: Dangerous voltages and currents are transmitted by the
Terrameter via the electrode cables connected to the Electrode
Selector! During the entire duration of an electrode contact test
or measurement session it is the responsibility of the operator
always to have full control of the entire electrode cable layout, so
that people and animals do not get close to the electrodes and
electrode take-outs connected to the measurement cables!
6.2.6
Electrode Test
If the electrode test (as described above) is set to
Yes
, the system checks if it is possible to
transmit current through all electrodes. This test only takes a couple of minutes, but can save a
lot of time afterwards!
The array code determines how the contact test is performed. For most arrays the electrodes
can be tested pair-wise against each other starting at one end. Another option is to test each
electrode against all the other electrodes (only available for ES10-64). For pole-pole and pole-
dipole all the electrodes are tested individually since one of the current electrodes is assumed
to be a remote electrode.
If long cables (e.g. with 5 meters or more between take-outs) are used a set of walkie-talkies
are useful for efficient work, otherwise a lot of time may be wasted running up and down the
cables.
The program automatically continues to measure using all four electrode cables when the
contact is satisfactory. Occasionally, the program may stop depending on poor electrode
contact even if the contact test was passed (depending e.g. on drying out, or that two "half-
poor" electrodes are used together). It is therefore advisable to check that measurements have
not stopped every now and then, and improve contact (or step down the current for that
particular electrode combination only). It may be wise using a one step higher “lowest
permissible current” during the Electrode Test and then return the value to the ideal, before
the measuring starts.
