Users’ Manual
EDS-71V/P Single point borehole extensometer
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14
NOTE:
Holes on top of flanged housing are marked
clockwise with identification numbers 1, G
respectively and V in middle. As an Encardio-rite
convention, serial number ‘1’ always
corresponds to anchor.
As an additional precaution, make a note in a
diary of orientation of serial number ‘1’ with
geographical North.
NOTE:
When BHE is installed on a side wall or roof,
extension is generally expected. In such a case,
it may be desirable to set connecting rod end as
close as possible to reference plate (14).
Similarly, when BHE is installed in a vertically
down borehole settlement is generally expected.
In such cases, it may be desirable to set
connecting rod end as close as possible to guide
plate (6). In other cases, it may be necessary to
set connecting rod end in middle such that either
compression or tension can be monitored.
In other words, if only compression is expected,
set zero reading of sensor by extending shaft by
around 10 mm. If only extension is expected, set
zero reading of sensor by extending shaft by
around 10 mm less than sensor range. If
required, sensor may be set in mid position. As
a precaution, never set the sensor at the very
end.
A set of 100 mm or 125 mm or 150 mm long
cheese head screws (24) and lock nuts (25) is
provided for this purpose.
3.3.9 For any other required range, set distance ‘C’
accordingly. For example, Assemble cheese head
screw (24) and locking nuts (25) as shown in figure
3.2. Slightly loosen hollow bolts (12) related to hole
‘1’. Adjust end of connecting rod in required position
and tighten the lock nuts (25). To set connecting rod
ends, refer to table above.
Sensor range
(A)
Setting range
(B)
Shaft end from
guide plate top
(C)
50 mm
± 25 mm
45 mm
100 mm
± 50 mm
70 mm
150 mm
±
75 mm
95 mm
Reference
plate
Guide plate
Downward borehole
+40
0
-10
~1
0
Tube face
30
Mid position borehole
+25
0
-25
~1
0
Tube face
45
Upward borehole
-40
0
+10
~1
0
Tube face
60
