Accessing channel parameters with logicpro, Channel parameters for heat and cool outputs, Channel parameters – Watlow PPC-2000 User Manual

Page 199: Accessing channel parameters with, Logicpro

Advertising
background image

PPC-2000 User’s Guide

Chapter 5: LogicPro and Modbus Reference

Doc.# 30002-00 Rev 2.3

Watlow Anafaze

173

Accessing Channel Parameters with

LogicPro

When a logic program variable accesses a channel parameter,
the parameter number (#) and the channel number (database
offset) are used in conjunction with the LogicPro’s Database
IO Driver. The IO Physical Address is constructed from the
parameter number and the channel number.

See the LogicPro User’s Guide for specific instructions on
addressing channel parameters. See Table 5.12 on page 174 for
channel parameter numbers.

Channel Parameters for Heat and Cool Outputs

Each of the PPC’s closed-loop control channels may have one or
two outputs (heat and/or cool). Many of the channel parameters
may be independently set for the heat and cool outputs and,
therefore, have two registers in the database. For example, Heat
Proportional Band (Heat Prop Band) is the proportional band for the
heat output and Cool Proportional Band (Cool Prop Band) is the
proportional band for the cool output.

Channel Parameters

Table 5.12 lists the parameter number (#), range, and first and
last Modbus addresses for each channel parameter. These
values are used when accessing channel parameters with
third-party software, operator interface terminals or LogicPro
programs.

The range of some of the parameters is equal to the range of the
input type selected for the channel. See Table 5.10 on page 170
for a list of the input types and their corresponding ranges.
While all the channel parameter values are 16-bit integers,
many, such as Control Mode, are numerical representations of
settings that have special meanings to the controller. See the
tables under the corresponding parameter descriptions for
explanations of the possible settings.

Advertising