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Using the io drivers, Cpc400_pv, Table 12.14—address syntax for database driver – Watlow LogicPro User Manual

Page 226: For a description of this syntax

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Chapter 12: Function Blocks

LogicPro User’s Guide

210

Watlow Anafaze

Doc.# 28002-00 Rev 3.00

Table 12.14 Address Syntax for Database Driver

Two types of parameters are accessed using the Database I/O driver:
Channel and Global. The following sections describe how to
determine the database offsets to be used to access each of these
types of parameters.

Parameter Number

The parameter number is the numeric identifier used to
address a closed-loop control parameter. Each parameter in
the CPC400 has a parameter number. See the CPC400 manual
for a list of parameter numbers and descriptions.

Database Offset

The database offset is the location of a particular value
relative to the first value of that parameter. For example, each
channel has a proportional band setting. If you want to set the
proportion band for channel 6, the address will include the
database offset 6.

Channel Parameters

The database offsets associated with channel parameters are
the channel numbers. Refer to the CPC400 Series User's
Guide for a complete description of channel parameters and a
list of channel parameter numbers.

Global Parameters

Global parameter offsets are dependent on the global
parameter. See the CPC400 Series User's Guide for a
complete list of global parameter numbers and their
corresponding offsets.

Using the IO Drivers

The following sections describe and illustrate the use of each
IO Driver.

CPC400_PV

The CPC400_PV driver allows a logic program to access the
process variables (PV) for each channel.

To read a PV with a logic program variable:

1.

Open the

Add Program/Resource Variable

dialog box.

2.

Enter a unique variable

Name

.

Syntax

Used with this IO Driver

#.D

# = Parameter Number
D = Database Offset

Database