abem Terrameter LS, Инструкция по эксплуатации

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ABEM Terrameter LS
102
Note that the pins 22-32 in the standard cables with 21 take-outs each are not
connected to any electrode take-outs, but used for linking every second take-out on
the outer electrode cables to the Terrameter / Electrode Selector via the cable joints.
12.11 Protocol Files in ORG-format
The format of protocol files in the system used by older versions of the ABEM Lund
Imaging System is presented here for reference since one way of creating an XML-
format protocol file is to convert from this format. The first station (midpoint
position) is always measured using a protocol file with .ORG filename extension.
Consecutive stations use .UP or .DWN protocol files depending on if the roll-along is
done towards higher or lower coordinates. The .UP or .DWN files are reduced
according to the possible data overlap with the previous station, to avoid measuring
the same data points twice. This also means that measuring is normally much faster
for consecutive stations at a roll-along than for the first. Terrameter LS automatically
reduces the measurements at consecutive stations for overlap with measurements
already taken at previous stations, so it is only necessary to convert the ORG-file
If more than one protocol file is used for each station there is also a possible overlap,
between the protocol files at the same midpoint, as for example when doing Wenner
CVES with long and short layouts. In this case one of the files should be reduced
accordingly.
The protocol files contain an array code, the address file used followed by a comment
string, and the logical positions of the electrodes. The positions are given for the
current electrodes followed by the position of the potential electrodes. The format is
thus:
code [arraystring]
addressfile [commentstring]
Apos(1) Bpos(1) Mpos(1) Npos(1)
Apos(2) Bpos(2) Mpos(2) Npos(2)
...
Apos(n) Bpos(n) Mpos(n) Npos(n)
where the electrode positions are given as integers in the interval 1- n
tot
. If remote
electrodes are used these positions are specified as zero.
The array codes are used mainly for presentation purposes, and in the case of pole-
pole and pole-dipole how the contact test is performed. The array codes used for
Terrameter LS are compatible with Res2dinv, and they differ from what is used by
Terrameter SAS1000 / SAS4000. The following codes are defined:
Electrode
Array Array
Code Code in Old
System
Resistance 0 0
Wenner-
α
1 1
Pole-Pole 2 4
Dipole-dipole 3 5