ABEM Terrameter SAS 1000 / SAS 4000
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6.2.7
Speed Up the Field Procedure
A good way to speed up the field procedure is to have one extra electrode cable and a
generous supply of electrode and cable jumpers available, so that the extra cable can be rolled
out and hooked up to electrodes while measurements are in progress. In this way the
instrument and cable joints can simply be moved one step before starting the roll-along
measuring on the following measurement station. If no extra electrode cable is at hand the
following procedure can be adopted.
While the measurements are in progress for the long layout (using all four cables) the
electrodes for the remaining take-outs on the two electrode cables closest to the centre (short
layout) may be connected. When measurements are done for the long layout, the program
stops and waits for the operator to press
to continue with protocol file #2 if "Wait between
protocols" is set to YES.
As soon as the measuring on the long layout is finished, Cable 1 can be disconnected, wound
up and rolled out ahead of Cable 4 (if you want to perform roll-along). In this way all
electrodes can be in place when measurements on the short layout are finished. Bring along
the cable joint used to link Cable 1 and Cable 2 and drop it at the Electrode Selector.
Disconnect the other cable joint when passing the connection between Cable 3 and Cable 4,
and use it for linking the former Cable 1 when it is in place in the position ahead of Cable 4.
Make sure that what is now Cable 3 and Cable 4 are linked together with a cable joint, unless
it is the last station on the profile and Cable 4 hence is excluded.
When all measurements on the short layout are finished, the program stops and asks whether
to continue with roll-along measurements (upward or downward) or quit. If you want to link
more data to the profile, first disconnect Cable 2 and Cable 3 from Electrode Selector, and
link these cables together with the cable joint. These cables are from now Cable 1 and
Cable 2! Move Electrode Selector and Terrameter to the new centre point, and connect what
is now Cable 2 and Cable 3 to Electrode Selector.
If you decide to continue with roll-along (up or down) the Measurement Setup menu appears
again. The same comments as described previous applies. The process now continues as
described above: checking of contact and measuring first for long layout and then short
layout. However, measuring is now faster since many possible measurement combinations
were already measured in the previous layout. While measuring is carried out on the long
layout all electrodes at even-numbered take-outs on Cable 1 can be removed and connected to
the even-numbered take-outs on Cable 3, to be ready for the contact test for the short layout.
The profile can be extended as far as desired. In addition measuring can be stopped at any
time by pressing
, which gives a possibility to change certain parameters in the setup. The
measurement can then be continued, by pressing the
key.
While measuring the profile, do not forget to take notes of the position of reference points
along the line using the cables as ruler. Do also mark out some of the used midpoints along
the profile with pegs, sticks, paint or whatever is suitable. This facilitates identification of
points for further investigations later on. Furthermore, it is often efficient to level the
topography while doing the measurements, using the cables as ruling tape. Similarly it can be
efficient to determine the coordinates of key points along the measured line with GPS during
the measurement process, unless this is taken care of by a special arrangement.
It is possible to stop the measuring program at any point, and re-start it again. You can select
an existing record and add data to this record. The program will automatically find out how
far the surveying has proceeded, update coordinates etc. It is thus possible to continue
surveying without loosing data after e.g. a power failure, or to extend a profile the next day. A
profile can be extended either towards increasing coordinates (up) or decreasing coordinates
