Honeywell UDC2800 Product Manual page 101

Chapter 4 - Configuration
Function Prompt
101
Selections or Range of
Setting
Feedforward Mult
(Standard feature on
controllers with two
analog inputs)
Summer
(See Note 2)
High Select
(See Note 2)
Parameter Definition
Three Position Step Control
applications.
The following formula applies:
Controller Output = PID Output +
(Input A x Ratio A + Bias A ) x (100 /
Input A Range)
Feedforward Multiplier —
Feedforward uses Input A, following
a Ratio and Bias calculation as a
value multiplied directly with the PID
computed output value and sent, as
an output value, to the final control
element.
This algorithm will only function in
automatic mode and is not used for
Three Position Step Control
applications.
The following formula applies:
Controller Output = PID Output x
(Input A x Ratio A + Bias A ) / Input A
Range
Summer with Ratio and Bias —The
following formula applies:
Alg1 = (Input A x Ratio A + Bias A) +
(Input B x Ratio B + Bias B) + (Input
C x Ratio C + Bias C) + Alg1Bias
Input High Select with Ratio and
Bias —This selection specifies the PV
or SP as the higher of Input 1 or
Input 2. The following formula
applies:
Alg1 = higher of (Input A x Ratio A +
Bias A) or (Input B x Ratio B + Bias