ABB COMMANDER C355 - Appendix B: COMMANDER Configuration Editor; Introduction to Configuration Editor; Analog Input Customization; Programmable Math Blocks and Logic Equations

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APPENDIX A – CONTROL TEMPLATES…
PID O/P
CSPt
L
L
R
PV
I/P1
Manual Output
OP1
Local Ratio
Remote Ratio
Process Variable input
PV – bIAS
WV
I/P2
Wild Variable
rAtO
WV
Actual
Ratio
•1
•1 Template 15 only
Actual – Desired
Ratio
WV x rAtO + bIAS
PID
Control Loop
Profile Set Point
I/P3
A7 Ratio Controller (Templates 14 and 15)
The Ratio Controller enables a controlled process variable to be maintained automatically in definite proportion to another variable known as the w
ild
variable. The wild variable weighted by ratio (
rAtO
) and bias (
bIAS
) values forms the control set point for the process variable. The ratio value applied
to the wild variable can be either a local value set on the front panel or a remote signal on an analog input.