Honeywell UMC800 Reference Guide

Function Blocks
Function Block Reference Guide 3/99214
2.74 TPSC (3POS) Function Block
Description
The
TPSC (3POS)
label stands for
Three Position Step Control
operation. This block is part of the
Loops
category. It looks like this graphically on the Control Builder
Function
This block combines a PID controller with 3 position step control output functions to provide motor
position control without position sensing. Allows the control of a valve or other actuator having an electric
motor driven by two digital output channels; one to move the motor upscale, the other to move it
downscale, without a feedback slidewire linked to the motor shaft.
Inputs
PV
= Process Variable Analog Input value in Engineering Units
RSP
= Remote Setpoint Analog Input value in Engineering Units or Percent
TRV
= Output Track value in Percentage (PID Output = TRV Input when TRC = ON.)
TRC
= Output Track Command [ON, OFF] (On -Enables TRV.) (Mode = Local Override)
BIAS
= Remote Bias value for Ratio PID
SWI
= Switch Inputs (from SWO on LPSW function block)
0 = No Change
1 = Initiate Autotuning
2 = Change Control Action
4 = Force Bumpless Transfer
8 = Switch to Tune Set 1
16 = Switch to Tune Set 2
MDRQI
=External Mode request (typically connected to the MDRQO output of a MDSW function block.
0 = No Change
1 = Manual Mode Request
2 = Auto Mode Request
4 = Local Mode Request
8 = Remote Mode Request

Honeywell UMC800 Specifications

General

Brand	Honeywell
Model	UMC800
Category	Controller
Language	English