18
SYSTEM
Figure25 Sensor head external components
Figure26 Sensor head internal components
The cable and the sensor head electronics are connected and the cable and cable strain
relief are not designed to be disconnected from the sensor head. Keep the strain relief
screwed into the sensor head firmly.
The SC-1 relies on a measurement of the RH gradient between the leaf evaporating surface
and the desiccant chamber. The use of the desiccant chamber lowers the ambient RH to near
0%, thus ensuring a steep RH gradient between the leaf and desiccant chamber. Although
several different desiccants may work in the SC-1 (e.g., silica gel and Drierite
®
), METER
recommends molecular sieve 8-12 mesh because it has the best combination of sorption
rate and total water sorption properties for this application.
NOTE: For the molecular sieve safety data sheet (SDS), a printable version is available at metergroup.com/
environment/meter-safety-data-sheets.