ABEM Terrameter SAS 1000 / SAS 4000
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9.5
PERIODIC CHECKS
9.5.1
Terrameter SAS 1000 / 4000 - Check
The proper functioning of most of the SAS 1000 / 4000 circuitry can be checked using
reference resistors and a capacitor having known values. This test should be performed at
least once per year. The following test assumes access to a Multi Channel Adapter (optional
accessory 33 0020 02), but similar tests can be carried out for channel 1 (CH1) with test
separate resistors.
Two resistors and one capacitor are built into the Multi Channel Adapter. Their nominal
values are:
Between terminals: Resistance: Capacitance:
T1 and T2
1
no
T3 and T4
15 k
1
F
T2 and T4
15
no
The following procedure will check the SAS 1000 / 4000 and also check the values of the
above components. Enter the readings in the table below.
To perform the test you need at least four test cables with banana plugs or fork connectors.
Proceed as follows:
1.
Connect P1 from e.g. CH1 to T3.
2.
Connect P2 from e.g. CH1 to T4.
3.
Connect C1 to T3 and C2 to T4.
4.
Perform a resistivity measurement using AUTO output current and enter the reading in the
table below
5.
Perform a IP measurement using AUTO output current (one time window, from 10 msec to
110 msec) and enter the reading in the table below
6.
Repeat step 1-4, but with the cables connected to T1 and T2.
7.
As in 6, but with cables connected to T2 and T4.
8.
If you are testing a SAS 4000 move the connectors from CH1 to CH2 (and after that to
CH3 and CH4) and repeat step 1-7.
Write down the measured values in this table for future reference:
CH1
CH2
CH3
CH4
Expected
T3 - T4, resistivity
R =
15
k
T3 - T4, IP
M
10,110
=
7.7
msec
T1 - T2, resistivity
R =
1
T2 - T4, resistivity
R =
15
