Decagon EC-5 - Page 19

6 CALIBRATION EC-5
for a Decagon data logger or
θ = 2.11 x 10
−3
∗ mV − 0.675 (6)
for a data logger with 2,500 mV excitation.
Rockwool
We calibrate the EC-5 in Grodan Master rockwool with solution
electrical conductivities of 0.2, 1.0, 1.5, 2.0, and 4.5 dS/m. VWC
can be calculated using
θ = 6.28 x 10
−7
∗ RAW
2
+ 1.37 x 10
−4
∗ RAW − 0.183 (7)
for a Decagon data logger or
θ = 2.63 x 10
−6
∗ mV
2
+ 5.07 x 10
−4
∗ mV − 0.0394 (8)
for a data logger with 2,500 mV excitation.
Note: These calibration constants only apply to 2,500 mV excita-
tions; use of these numbers with any other excitation voltage results
in erroneous readings!
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