Preliminary User Manual UMAX023241 - Version: 1.1 22-63
1.7.
Math Function Block
Figure 12: Math Function Block objects
There are two mathematical function blocks that allow the user to define basic algorithms. A math
function block can take up to five input signals. Each input is then scaled according to the associated
limit and scaling setpoints.
Inputs are converted into percentage value based on the “Function X Input Y Minimum” and
“Function X Input Y Maximum” values selected. For additional control the user can also adjust the
“Function X Input Y Scaler”. By default, each input has a scaling ‘weight’ of 1.0 However, each input
can be scaled from -1.0 to 1.0 as necessary before it is applied in the function.
For example, in the case where the user may want to combine two inputs such that a quadrature
Encoder speed (Input 1) is the primary control of an output, but the speed can be incremented or
decremented based on the quadrature Encoder step count (Input 2), it may be desired that 75% of
the scale is controlled by the Encoder speed, while the current step count can increase or decrease
the min/max output by up to 25%. In this case, Input 1 would be scaled with 0.75, while Input 2 uses
0.25. The resulting addition will give a command from 0 to 100% based on the combined positions
of both inputs.
A mathematical function block includes four selectable functions, which each implements equation
A operator B
, where A and B are function inputs and operator is function selected with setpoint
Math
function X Operator
. Setpoint options are presented in the table below. The functions are
connected together, so that result of the preceding function goes into Input A of the next function.
Thus Function 1 has both Input A and Input B selectable with setpoints, where Functions 2 to 3 have
only Input B selectable. Input is selected by setting “
Function X Input Y Source
” and
Function X
OBJECT
DICTIONARY
APPLICATION
Local Control
Signal
Local Control
Signal(s)
CAN BUS
7300h
AO
Output
PV
RPDO
2502h
Digits
Extra
3yz8h
Y
‐
Axis
PV
6220h
DO
Write
State
6302h
Digits
PV
4000h
Enabled
4x00/01/02h
Input
1
Src/Nmbr/Fcn
4032h
Digits
PV
2450h
Extra
PV
4x00/01/02h
Input
2
Src/Nmbr/Fcn
4x00/01/02h
Input
3
Src/Nmbr/Fcn
4x00/01/02h
Input
4
Src/Nmbr/Fcn
4x00/01/02h
Input
5
Src/Nmbr/Fcn
4x00/01/02h
Input
6
Src/Nmbr/Fcn
4x03/20/22/40h
Input
1
Scaling/Gain
RPDO
RPDO
TPDO
4x03/20/22/40h
Input
2
Scaling/Gain
4x03/20/22/40h
Input
3
Scaling/Gain
4x03/20/22/40h
Input
4
Scaling/Gain
4x03/20/22/40h
Input
5
Scaling/Gain
4x03/20/22/40h
Input
6
Scaling/Gain
4x50h
Operator
1
4x50h
Operator
2
4x50h
Operator
3
Math x
Function 1
Math x
Function 2
Math x
Function 3
Math x
Function
Result
Math
Local Signal
FV to PV
Calculation
4021h
Scale
1
PV
4023h
Scale
2
PV
