Response Electronics CL6011B Especificaciones descargar pdf (Pagina 36)

3Ć16 Theory of Operation: Point Processing

Original Ć June 1990CE4.2:CL6211

The Control Sequence PCA allows the user to customize the PCA

computation to perform any unique control algorithm. A minimum set of

standard features are provided by the CONTROL and STATION FST

function blocks when the Control Sequence PCA type has been

selected. These standard features include Operating Parameter display

and communications support (PV, SP, IVP, Mode, Bias, and Ratio),

parameter limiting, alarming, tracking, etc.

3.3.1.9.1 FST Configuration using Control Sequence PCA

The user may program any set of computations between the CONTROL

and STATION FST blocks, using the standard FST functions. This is

different from the normal" PCA types, which will NOT allow the user to

program any FST functions between the CONTROL and STATION FST

blocks. These configuration restrictions are as follows:

Standard PCA Types Control Sequence PCA Types

CNTRL

STAT

Only feedforward

FST function blocks

allowed here.

CNTRL

STAT

Any FST function

EXCEPT feedforward

allowed here.

Notice that the FST will not allow the user to configure any feedforward

FST function block into this loop when the Control Sequence PCA type is

selected. The user must accommodate any feed forward action required

by including the FST logic necessary to support that feed forward action.

3.3.1.9.2 Equations for CONTROL FST Function Block

The Signal Value Analog (SVA) output of the CONTROL FST function

block for a Control Sequence PCA type is equal to the loop deviation

error (PV minus SP for direct action, or SP minus PV for reverse action).

The SVA output value is always a percent deviation signal, computed

after the PV and SP have been converted to percent on the Engineering

Units scale. The Signal Value Discrete (SVD) output of the CONTROL

FST function block is set to zero when the PCA is being initialized (such

as after a power fail restart, or after any mode change is received), and is

set to one whenever the PCA is performing all normal forward

1 2 ... 31 32 33 34 35 36 37 38 39 40 41 ... 319 320

Sin comentarios

Response Electronics CL6011B Especificaciones Pagina 36