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Software

• Upper-Lower – Uses both the Upper Temperature Limit

(upperThreshold) and Lower (Base) Temperature (lowerThreshold) to

calculate the GDD. The method of calculation changes based on both the

Temp Values to Use field and the Cutoff Method field as described

below:

o Average Temperature

 None – Not adjusted for upper threshold. Basically the

same as the Simple GDD Method.

 Horizontal – If (Tmean > upperThreshold) then

Tmean = upperThreshold

 Intermediate – If (Tmean > upperThreshold) then

Tmean = Tmean – (Tmean – upperThreshold) * 2

 Vertical – If (Tmean > upperThreshold)

then GDD = 0

The GDD is then calculated as follows:

If (Tmean > lowerThreshold) then

GDD = (Tmean – lowerThreshold) * dataInterval

Else

GDD = 0

o Min/Max Temperature

 None – Not adjusted for upper threshold. Basically the

same as the Simple GDD Method.

 Horizontal – If (Tmax > upperThreshold) then

Tmax = upperThreshold

 Intermediate – If (Tmax > upperThreshold) then

Tmax = Tmax – (Tmax – upperThreshold) * 2

 Vertical – If (Tmax > upperThreshold) then

GDD = 0

If the above calculation causes Tmax to be below Tmin, then

Tmin is set equal to Tmax.

The mean value is calculated from this new Tmax and Tmin:

Tmean = (Tmax + Tmin) / 2

The GDD is then calculated as follows:

If (Tmean > lowerThreshold) then

GDD = (Tmean – lowerThreshold) * dataInterval

Else

GDD = 0

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Campbell CS105MD Spécifications Page 31