Campbell Scientific Sentek TriSCAN® Manual v 1.2a - Manual (Page 36)

TriSCAN Manual Version 1.2a
Copyright © 1991 – 2004 Sentek Pty Ltd All rights reserved Page 29
11. Use a sledgehammer to tap the dolly until the access tube is embedded approximately 5 cm into the
soil.
12. Place the auger inside the access tube and turn the handle clockwise. Auger ahead of the access
tube by approximately 20 cm (until the pen mark made in step 6 is flush with the top of the access
tube).
13. Take the auger out of the tube and empty the soil using the small auger cleaning tool No. 1.
14. Select dolly No. 1 or dolly No. 2 and re-insert into the top of the access tube.
15. Use the sledgehammer to drive the access tube further into the predrilled hole.
16. When you reach the bottom, remove the dolly. Again, auger ahead of the access tube by
approximately 10-20 cm. Alternate between augering and hammering until the dolly resting on top
of the access tube touches the top of the tripod.
17. Insert dolly No. 3 and continue hammering and augering until the mark on the dolly is level with the
top of the tripod.
18. Remove the tripod by inserting the tommy bars into the holes of the tripod pins and pulling them
upward with a twisting motion.
19. When all pins are removed carefully lift the tripod straight upward and off the access tube.
20. Try twisting and moving the access tube. It should not move and there should be no air gaps.
21. If there is an air gap, retrieve the access tube and start the installation process again at a site at
least one metre away from the failed installation.
Cleaning the Access Tube
The access tube must be cleaned before the top cap is installed and readings are taken. The bottom stopper
is installed after cleaning in all soils except very wet and saturated soils. The type of soil at the installation
site will determine which of the three cleaning methods is to be used. For instance, for dry/moist sandy to
loamy conditions:
1. Attach cleaning tool No. 1.
2. Remove loose soil, dry sand etc from the bottom of the access tube by turning the tool a few times
until the sand collects on top of the spiral. Pull up and retrieve the material.
3. Select the access tube cleaning tool No. 3 – rag tool. Insert a clean cotton cloth into the eyelet and
saturate with methylated spirits (denatured alcohol). Move this tool up and down the access tube to
clean off the final dirt residue from the access tube.
4. After cleaning the tube, inspect the inside of the access tube with a light. You should be able to see
clean walls and the lip of the cutting edge at the bottom.
Installing the Bottom Stopper Bung
The bottom stopper bung is installed after the access tube has been cleaned. To install the bung:
1. Partially insert the bung into the access tube and hold it at the upper end so that 75% of the top
rubber ring is within the access tube.
2. Tighten the wing nut to the point where there is enough friction on the wall of the access tube to
prevent the bung from turning in the tube while the wing nut is tightened.
3. Attach the bung tightening tool to the auger extension rod and use the tommy bars to tighten it
firmly.
4. Place the bung tightening tool over the wing nut and slowly push the bung down the access tube.
Allow air to escape until the bung rests on top of the internal cutting edge on the inside of the tube.
5. Slowly turn the T-handle clockwise until you feel resistance to turning when the bung is sitting tight.
6. Twist the tool clockwise quickly while pulling upwards. This will release the spring on the tool from
the wing nut and enable you to pull the tool out of the access tube.