Lws-l dielectric leaf wetness sensor, General description, Specifications – Campbell Scientific LWS Decagon Leaf Wetness Sensor User Manual

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LWS-L Dielectric Leaf Wetness Sensor

1. General Description

Direct measurement of leaf wetness is problematic. Secure long-term
attachment of a sensor to a representative living leaf is difficult. Leaf position,
sun exposure, and health are in constant flux. To avoid these problems, leaf
wetness “sensors” have been developed to estimate by inference the wetness of
nearby leaves. The LWS-L estimates leaf surface wetness by measuring the
dielectric constant of the sensor’s upper surface. The sensor is able to detect
the presence of miniscule amounts of water or ice. Individual sensor
calibration is not normally necessary.

2. Specifications

Measurement Time:

10 ms

Excitation:

2.5 VDC (2 mA) to 5.0 VDC (7 mA)

Minimum Excitation Time:

10 mS

Output:

10% to 50% of excitation

Operating Temperature:

-20 to 60 °C

Probe Dimensions:

11.2 cm x 5.8 cm x .075 cm

Datalogger Compatibility:

CR10X, CR200, CR800, CR1000, CR3000,
CR5000

Maximum Lead Length:

250 ft

Interchangeability:

Interchangeable without painting or individual
calibration