Special command and status blocks – Rockwell Automation 1771-QDC, D17716.5.87(Passport) CLAMP AND EJECT MODE User Manual
Page 55

Overview of the Remaining
Configuration Procedures
Chapter 4
4-2
There are two basic types of command blocks. They are presented in the
following table:
Type:
Which Contain:
Examples:
Configuration Blocks
Information necessary to configure your
module to run a certain portion of a profile
Valve spanning
information for the 1st
clamp close profile
Profile Blocks
Actual process setpoints necessary to
produce a desired part.
1st clamp close profile
operating setpoints
Status Blocks
The QDC module returns critical operating status and values to the PLC
data table through status blocks. Like configuration blocks, status blocks
are areas of PLC data table. Status blocks, however, contain actual
machine operation information rather than machine setpoints and action
commands.
Type:
Which Contain:
Examples:
Status Blocks
Information about machine operation and
QDC module operating status.
The molding machine is
currently performing an
ejection operation.
A few special command and status blocks are the Module Configuration
Block, Dynamic Command Block, and the System Status Block.
Types:
Description:
Examples:
Module Configuration
Block (MCC)
Contains configuration information used
throughout all phases of machine
operation
Sensor spanning information
and global alarm setpoints
Dynamic Command
Block (DYC)
Includes all commands necessary to jog,
run, and stop any applicable machine
phase or operation.
Request that the ejectors
advance
System Status Block
(SYS)
Returns to the PLC processor information
relevant to common module parameters.
Actual voltages and
engineering units read back at
the four QDC module inputs
Special Command and
Status Blocks