Output Splitter Function Block - Fisher FIELDVUEDVC6200f Instruction Manual

Instruction Manual
D103412X012

Output Splitter Function Block262.

Overview
The Output Splitter (OS) block (figure E‐15) provides the capability to drive two control outputs from a single input.
Each output is a linear function of some portion of the input. Back calculation support is provided using the same linear
function in reverse. Cascade initialization is supported by a decision table for combinations of input and output
conditions.
Figure E‐15. Output Splitter (OS) Function Block
RCAS IN
CAS IN
This block is normally used in split ranging or sequencing of multiple valve applications. A typical split range
application has both valves closed when the splitter input is 50%. One valve opens fully as the input drops to 0%. The
other valve opens as the input rises above 50%.
A typical sequencing application has both valves closed at 0% input. One valve fully opens as the input rises to 50% and
the other stays shut. The second valve opens as the input rises above 50%, and the first valve may remain open or shut
off quickly.
Because this block is in the control path, it is able to pass limit and cascade initialization information back to the
upstream block. Table E‐20 lists the OS block parameters and their descriptions, units of measure, and index numbers.
Figures E‐16 and E‐17 illustrate the internal components of the OS function block.
OS
OUT 1
OUT 2
DVC6200f Digital Valve Controller
OS Function Block
February 2017
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