Campbell Scientific CR5000 Measurement and Control Module - Manual (Page 122)

Section 6. Data Table Declarations and Output Processing Instructions
6-28
Parameter
& Data Type Enter
Repetitions
Constant The name of the data table to clone. The length of this name should be 4 characters or
less so the complete names of the worst case tables are retained when collected (see
NumCases).
Speed/East
Dir/North
Variables or
Arrays The source variables for wind speed and direction or, in the case of orthogonal sensors,
East and North wind speeds. If repetitions are greater than 1 the source variables must be
arrays containing elements for all repetitions.
DataType A code to select the data storage format.
Constant Alpha Code Numeric Code Data Format
IEEE4 24 IEEE 4 byte floating point
FP2 7 Campbell Scientific 2 byte floating point
DisableVar
Constant,
Variable, or
Expression
A non-zero value will disable intermediate processing. Normally 0 is entered so all inputs
are processed. For example, when the disable variable is
≠
0 the current input is not
included in the total. The total that is eventually stored is the total of the inputs that
occurred while the disable variable was 0.
Value
Result
0 Process current input
≠
0 Do not process current input
Subinterval
Constant
The number of samples per sub-interval calculation. Enter 0 for no sub-interval
calculations.
SensorType The type of wind sensors
Constant Value Sensor Type
0 Speed and Direction
1 East and North
OutputOpt Value Outputs (for each rep)
Constant 0 1. Mean horizontal wind speed, S.
2. Unit vector mean wind direction,
Θ
1.
3. Standard deviation of wind direction,
σ
(
Θ
1).
Standard deviation is calculated using the Yamartino algorithm. This
option complies with EPA guidelines for use with straight-line Gaussian
dispersion models to model plume transport.
1 1. Mean horizontal wind speed, S.
2. Unit vector mean wind direction,
Θ
1.
2 1. Mean horizontal wind speed, S.
2. Resultant mean wind speed, U .
3. Resultant mean wind direction,
Θ
u.
4. Standard deviation of wind direction,
σ
(
Θ
u).
This standard deviation is calculated using Campbell Scientific's wind
speed weighted algorithm.
Use of the Resultant mean horizontal wind direction is not
recommended for straight-line Gaussian dispersion models, but may be
used to model transport direction in a variable-trajectory model.