Device Preparation; Insert Sensor Needle Into Sample Material - METER HYPROP 2 Application Note

16. It is important to let the sample saturate through capillary action. Do not pour water on
the top of the sample because air enclosures and the pores will not completely fill with
water (Figure 6).
17. Store the trough and the soil samples where they are not directly exposed to sunlight.
18. In case the material swells as it takes in water, place a weight on top of the sample to
keep it from floating or tipping.
19. Saturation is finished when the surface of the sample is glossy.

2.4 DEVICE PREPARATION

The HYPROP 2 sensor unit and its tensiometer shafts need careful preparation. Detailed
directions for preparing the tensiometer shafts and HYPROP 2 sensor unit are available in
the HYPROP User Manual section 2.5.

2.4.1 INSERT SENSOR NEEDLE INTO SAMPLE MATERIAL

NOTE: For a combined HYPROP 2 and VARIOS measurement of soil samples, only the TC-S70 sensor needle can be
used. This sensor comes as default with the VARIOS Complete Set and VARIOS Extension Set.
METER designed the VARIOS sensor to be easy to install and use. The sensor needle must be
inserted all the way into the sample material. Please observe the following considerations
when installing the sensor.
• Ensure there is a minimum of 1.5 cm of material surrounding the sensor needle in all
directions to avoid errors.
• Ensure there are no gaps around the sensor needle.
• Insert the sensor needle all the way into the sample material.
CAUTION
Bending the needle can damage any sensor beyond repair. If the needle becomes bent,
gently bend it back. A replacement may be needed if a needle is bent and no longer taking
good readings. Contact Customer Support for a replacement.
OPERATION
Figure 6 Soil sample in water trough
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