Io
SENSOR
Section 5 Geophone Testing
SMT-200 Operations and Technical Manual 2.00/R1
67
•
Next, invert each geophone one at a time and compare the
measured impedance value. The aim is to look at relative changes,
•
If there is one particular element that differs significantly from the
rest then consider this one as suspect. If all subsequent elements
read high or low then consider the first one as suspect. You may
have used the
bad
geophone to establish a reference.
This is very effective with series strings. Series parallel strings are a little more difficult as the good
branches tend to mask the bad one. In this case isolate the branch by laying down all the phones
within a branch to locate the bad branch. From there, once the suspect branch has been isolated,
proceed as above.
TIP
: When running the continuous impedance for fault finding use the
+/-
key instead of the
ENTER/START
. Using the
ENTER/START
key will cause the result of the test to be logged to the internal
memory. This technique can also be applied to regular tests as well.
--Test results--
No. 10
Temp 24.2
o
C
Imp
1724
ohm
<2069> <2153>
+/- New Ref
Now Testing
Cont Imp....
--Test results--
No. 10
Temp 24.2
o
C
Imp 2104
ohm
<2069>
<2153>
+/- New Ref
Now Testing
Cont Imp....
