UMAX130511 Version 1.00A Preliminary Documentation
– May be subject to change
44 - 141
8
XOR
True when InA/InB is True, but not both
9
+
Result = InA plus InB
10 -
Result = InA minus InB
11 x
Result = InA times InB
12 /
Result = InA divided by InB
13 MIN
Result = Smallest of InA and InB
14 MAX
Result = Largest of InA and InB
Table 32
– Object 4y50h Math Function Operators
For Function 1, InA and InB are Math Inputs 1 and 2, respectively.
For Function 2, InA is the result of Function 2 and InB is Math Input 3, respectively.
For Function 3, InA is the result of Function 3 and InB is Math Input 4, respectively.
For a valid result in each Function, both inputs must be non-zero value (other than
‘Control Source
Not Used’
). Otherwise, the co
rresponding Function is ignored, and the “Output Data” for the math
function block is the result of the earlier function scaled according to the output objects. For
example, if Math Input 4 is not used, the math output would be the result of the Function 3
operation.
For logical operators (6 to 8), any SCALED input greater than or equal to 0.5 is treated as a TRUE
input. For logic output operators (0 to 8), the result of the calculation for the function will always be
0 (FALSE) or 1 (TRUE).
Error data (i.e. input measured out of range) is always treated as a 0.0 input into the function.
For the arithmetic functions (9 to 14), it is recommended to scale the data such that the resulting
operation will not exceed full scale (0 to 100%) and saturate the output result.
When dividing, a zero InB value will always result is a zero output value for the associated function.
When subtracting, a negative result will always be treated as a zero, unless the function is
multiplied by a negative one, or the inputs are scaled with a negative coefficient first.
The resulting final mathematical output calculation is in the appropriate physical units using object
4021h
Math Output Scaling 1 PV
and 4023h
Math Output Scaling 2 PV
. These objects are also
considered the Min and Max values of the Math Block output and apply the resolution shift defined
by object 4032h
Math Output Decimal Digits PV
. The result is written to read-only object 4030h
Math Output PV
. These scaling objects should also be taken into account when the Math Function
is selected as the input source for another function block, as outlined in Table 17.
1.10. Miscellaneous Function Block
There are some other objects available which have not yet been discussed, or mentioned briefly in
passing (i.e. constants.) These objects are not necessarily associated with one another, but are all
discussed here.