chapter 4 qas system interfacing

Chrysler

Quality Alert System (QAS)

Users Manual

1 of 10

Chrysler QAS Revision: Rev.0

OFFICIAL: Chrysler UPDATED: June 2, 2009

Chapter 4 QAS System Interfacing

In This Chapter � Floor QAS PLC

� Direct Communication Module (DCM)

� Ethernet (ENET) Card

� QAS Workcell

� Plant Floor Communication System (PFCS)

Chrysler


Users Manual

2 of 10



Floor QAS PLC

Purpose The Floor QAS PLC is an Allen Bradley PLC-5, which communicates

with other components for the following reasons:

• To receive the vehicle bar code from the AVI/VMS driver

• To receive vehicle data (bar code) from the AVI/VMS WCC

• To receive the distance traveled by the conveyor encoders to

provide location information for the tracking image

• To send necessary information to the QAS WCC to track an image

along the conveyor and corresponding QAS stations

Floor QAS PLC Communication

Flow

AVI/VMS

Driver

QAS Tracking

Image

Application

Encoder

QAS WCC

AVI/VMS

SystemBar Code Label

Vehicle Data

Tracking Image

Distance

Traveled

Floor

QAS

PLC

Chrysler


Users Manual

3 of 10



Floor QAS PLC Panel

Chrysler


Users Manual

4 of 10



Direct Communication Module (DCM)

Purpose The DCM is a chassis-mounted, single-slot I/O module that allows

communication between the Floor QAS PLC and the AVI/VMS

Supervisor PLC.

The DCM passes data between the Floor QAS PLC and the AVI/VMS

driver. The Floor QAS PLC transmits data through the backplane of

the chassis to the DCM. The DCM transmits data via an Remote

Input/Output (RIO) connection to the AVI/VMS Supervisor PLC.

The DCM link number is an address that provides the AVI/VMS

Supervisor PLC with a source and return address for information

requested from the Floor QAS PLC.

Dual Inline Package (DIP) switches on the DCM set link numbers.

DCM Communication Flow

Floor QAS

PLC

AVI/VMS

Driver

Backplane

DCM AVI/VMS

Suprv PLC

DH+

RIO

DCM Communications

Flow

Chrysler


Users Manual

5 of 10



Direct Communication Module

Chrysler


Users Manual

6 of 10



Ethernet (ENET) Interface Module

Purpose The plant floor Ethernet connects the Floor QAS PLC to the QAS

WCC through the ENET Interface Module on the Floor QAS PLC.

This module is side-mounted to the Floor QAS PLC.

The Floor QAS PLC and the QAS WCC communicate over the plant

floor Ethernet.

The Floor QAS PLC requires a Transceiver Module to communicate

on the network.

Ethernet (ENET) Interface

Communication Flow

Floor QASPLC

ENET QAS WCC

Ethernet (ENET) Communications

Flow

Chrysler


Users Manual

7 of 10



ENET Interface Module

Chrysler


Users Manual

8 of 10



QAS Workcell

Purpose The QAS WCC is a pair of dual processor PC systems. The dual

systems form a standby recovery system, which provides high system

availability in the event of a fault. The secondary system is in standby

in the BIOS level of operations, which allows for a rapid startup in the

event of a loss of the primary machine.

The standby recovery system causes the secondary processor to boot

up upon the loss of the primary processor by:

Step Action

1 If the secondary system loses a heartbeat signal from the

primary processor, it finishes its boot process. As part of the

boot process, a service is started that sends a signal to the

UPS for the primary processor’s PCI bus. This signal causes

the UPS to remove power from the primary system’s

PCKXD card.

Note: If the secondary processor attempts to take control

before the primary’s PCI bus is powered down,

the secondary processor will see both its and the

primary’s PCKXD card. The memory address of

both cards is the same in the processor, which

would cause the secondary processor to

bluescreen, resulting in a loss of both processors.

2 After approximately 3 minutes, the secondary system

completes its startup and assumes control of the QAS WCC.

Chrysler


Users Manual

9 of 10



Software The QAS WCC contains the SoftLogix5 engine for operating QAS

control logic. SoftLogix5 runs on a PC computer that emulates an

Allen Bradley PLC-5/80. It runs as a service to the Windows NT

operating system, but will execute control logic in the same fashion as

a real PLC. QAS uses the SoftLogix5 engine instead of a real PLC for

these reasons:

• SoftLogix is able to connect to 36 I/O racks, as compared to 24 for

a real PLC.

• SoftLogix is able to make external auxiliary function (EAF) calls,

which means that SoftLogix is able to use additional programs

within its logic to determine outputs because it is processor-based.

SoftLogix5 also reads from a Realtime Database in the QAS WCC.

Currently, the Realtime Database is an Access97 database. The

SoftLogix5 engine communicates with the database in two ways:

• It uses ladder logic extensions (lgx) in the engine and

communicates via an ODBC/C++ DOA calls connection,

established in the workcell registry.

• It uses lgx in the engine and communicates via a Data Access

Object Software Development Kit (DAOSDK) connection. The

connection via ODBC is used for the workcell communications

with FIS, and the connection via DAOSDK is used for running the

database.

The QAS WCC also communicates with the Floor QAS PLC. The

QAS WCC receives the tracking image from the PLC and sequences

this image with the PFS terminals configured in the Realtime database.

In plants with ALS installed, the QAS WCC also sends the conveyor

run permissive signal to the Floor QAS PLC via a QAS sequence

panel.

Chrysler


Users Manual

10 of 10



QAS WCC Communications

Flow

QAS

WCCSoftLogix5

Engine

Realtime

Database

Floor QAS PLC

PFSPFCS

PFS

Terminal

The Realtime database in the QAS WCC communicates with a

Realtime database in the configuration database server. The Realtime

database in the configuration database server is copied to the QAS

WCC Realtime database using a Db copy utility. This action

minimizes the amount of time the Realtime database has to be down

for configuration changes.

Plant Floor Communication System (PFCS)

PFCS

PFCS provides a uniform store and forward function between plant

floor controllers, including the QAS WCC and PFS. Refer to PFCS

manuals for details.

chapter 4 qas system interfacing

Documents