Model 801 EM Current Meter
Page 20
© 2016 Valeport Ltd
below, which defines the type of fit.
Calibration
Function No.
OPERATION
0
Not defined
1
One straight line fit
2
Two straight line fit
3
Three straight line fit
4
Four straight line fit
5
Five straight line fit
The calibration takes the A/D counts, and calculates the engineering value from calibration
coefficients. In all cases it is assumed that the –ve and +ve flow characteristics are the same.
Thus, for example, a three line fit calibration will be entered in the format shown below (note the
single space between each value):
3 Coefficient1 Offset1 Max_lt1 Coefficient2 Offset2 Max_lt2 Coefficient3 Offset3
Max_limit3<cr>
The offset is the y axis [engineering value output] intercept at zero counts for the straight line
segment
The coefficient is the slope of the straight line in engineering units per count.
The limit is the number of counts up to which the straight line is to be used [must be a positive
number]
Where Max_lt is the range up to but not including, which the straight line operates over.
The first straight line starts from 0 up to Max_lt1 in A/D counts (WHOLE numbers).
The second straight line starts from Max_lt1 and including it up to Max_lt2 but not including it.
The third straight line starts from Max_lt2 and including it , up to Max_lt3 but not including it.
The last line limit [e.g. Max_lt3 in the example above] must be set to more than the maximum
number of counts, and Valeport usually use the figure 40000.