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Processing of Production Data
with a PC | |||
Using PLC systems for the control of productions processes and conveyor systems is a wellknown issue. Less popular are systems for the identification of parts and the control of the material flow. Without these systems an econimic management of the material and a coordinated Just in Time (JIT)-request cannot be achieved. | |||
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the main topics of a production control system the capturing and processing of data
regarding the utilization of production systems, the position of certain parts within the material flow
and the display of product relevant data can be found. When these applications are becomming too complex
for normal PLC systems a decentralised computer based solution; e.g. Data-Collection-Point (DCP) is to be chosen.
However, the performance and availability of these computer systems must be at least comparable with PLC systems.
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| Remote-Maintenance implemented | |||
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I.C.S. Industrielle Automatisierungssysteme GmbH based in Lehre (Germany), active now for more that
seven years in this scenario, provides with the development of her
Systemsoftware RTC-32 (Real-Time-Communication 32-Bit) an
Integration-Platform for complex production processes. The cooperation between I.C.S. and the
informationtechnology-provider Gedas NA in Puebla (Mexico), now active for six years, shows the possibilties
if this system. The software being used spans from simple applications with manual scanner handling,
automatic capturing supported by web-cameras and a remote emergency data entry,
applications for handling or monitoring of parts,
reading or writing of portable data carrier systems to
redundant Hot-Standby-Systems.
Based on the RTC-32 system a complete Remote-Maintenance-System has been implemented.
The software was developed as an Embedded System and does not require any operating system (OS).
It can be started as a Basic Input/Output System-Expansion
(BIOS) from the Bootsector of the hard disc, from an EPROM or by means of a special
Boot-Code under DOS. The internal structure of RTC-32 is very much compliant to the modular ISO/OSI-Layer model (Picture 1). RTC-32 is based on the Framework RTOS-32. Due to the standardized and hardware independent interfaces between the application modules the project definition and planning, coding, test and the final Rollout of the software can be achieved within a couple of days. | |||
| The RTC-32-System includes: | |||
| - internal TCP/IP-Stack for ISA- and PCI-Network interface cards
- TELNET Client-Server-Implementation - FTP Client-Server-Implementation for the remote maintenance, for example accessing parameter or log file stored on the local file system of the DCP | |||
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| The access control to the local file system is secured by MD5 encryption | |||
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User specific access rights have been implemented, all FTP actions are being logged in a separate log file.
- Web-Server - provides status informationen of the DCP for authorized HTML-Browsers. - SMTP-Implementation (Simple Message Transfer Protocol) sends error alerts via E-Mail to the maintenance personal. - SNMP V2-Implementation - parallel to the mail transmission alerts are being sent to an SNMP manager system. Since all of the remote maintenance features like HTTP, SMTP, FTP and TELNET can only be used as long as the network connection is not broken it was decided to add a server-side monitoring of the availability of the client (DCP) via the SNMP-Manager. | |||
| Factory Manager | |||
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Factory Manager, the Configuration- and Diagnosticsoftware from Phoenix
Contact for Ethernet-Networks in the Automatization Field, builds the
User-Interface to SNMP as a Front-End. It administers the Traps and
monitors the network availability of the DCP by means of Internet Control
Message Protocol telegrams (ICMP, Picture 2). The Factory Manager shows
the status of intelligent Infrastructure appliances (Switches) and
End-point devices (for example Industrial-PCs) and diagnoses critical
System conditions. An additional advantage comes into effect if the device network has been built using
Ethernet-Switches out of the Factory-Line product-family from Phoenix Contact.
In this case the informations are generated as textual messages and the devices can be addressed and monitored without any knowledge
regarding the Network structure and parameters (Picture 3).
Error messages generated by the RTC-32 system of the DCP and sent via E-Mail are forwarded directly to the personal pagers of the maintenance crew. Within a DCP-Installation the following components can lead to a stop of the conveyor lines in case of a fault: | |||
| - Computer - Dirty air filters used in conventional systems and an overheating of the CPU
- the Panel-PC PPC 5315 from Phoenix Contact does not have (and does not need) any filters
- Blower break down - Display break down - Un-interuptable power-supply (UPS) (for example a fault of the internal backup battery) - Digital I/O-System Interbus - Scanner-Systems - Read/Write-Systems for portable data carriers - Networkcomponents | |||
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| Also logical errors can have an impact on the functions of the DCP-Software:
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| - Communication problems with Host-Systems
- erroneous handling caused by the operator personal - wrong signal exchange with the PLC controlling the conveyor system, etc. | |||
| The software can not correct all problems, but the early diagnosis of potential problems and alerting the
maintenance team allows immediate corrective actions. Secondary damages like a permanent damage of PC components caused by overheating
or normally undetected stops of conveyor systems can be avoided.
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| Data capturing and processing with a Panel-PC
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| On the first glance one could say that standard office PC's are more
economical and of course until recently these hardware components have been used exclusively for DCP-Systems due to price and availability.
Unfortunately a PC system used in a normal office does not control its own components sufficiently and in some case
does not have sufficient slots for holding all required interface cards.
In order to overcome this situation three companies - Gedas-Mexico, I.C.S. and
Phoenix Contact - decided in 2003 to combine their efforts based upon the industrial PC hardware platform from Phoenix Contact for
DCP-Installations. The Panel-PC PPC-5315 offers all options required for
a remote maintenance strategy apart from its compact and industrialsuited building method. The available ISA- and
PCI-Slots of the passive Bussystem are more than sufficient for necessary expansion cards.
Phoenix Contact provides Panel-PCs, which are used for DCP applications ready for installation.
Together with the industrial PC all further components are integrated in a housing. The modulare System covers the entire spectrum
starting with simple decentralized Visualization applications up to complex central processing units.
Components like fieldbus, handling elements like switches and operating buttons,
keyboard, inter-connectivity elements, various Interface-Moduls and power supplies including UPS systems can be easliy integrated.
The products are being distributed through the worldwide network of Phoenix Contact. Also the
supply of spare parts and the service is absolutely no problem due to the worldwide presence of Phoenix Contact.
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The DCP software RTC-32 monitors certain hardware parameters like system-temperature,
the functionality of blowers and the display and generates alerts in case of any critical deviation via SMTP and SNMP.
The software is being self-controlled by means of an internal watchdog. The
integrated LCD-Display has a resolution of 1024x800 pixels and is equipped with a
touchscreen based on the serial EloTouch-Controller which enhances the ergonomical aspects of the unit.
In the basic configuration the PPC 5315 offers three free serial ports, COM4 is being used for the EloTouch Controller, one
Ethernet port (Realtek R8139), two USB-ports plus one Interbus-EcoLink-Treiber for the digital inter-connection with the PLC systems of the conveyor control.
This configuration, being used since the beginning of 2004 in a productive environment will be expanded and enhanced in the future.
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| Low Installation- and Maintenance costs | |||
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In spite of the fact that this combination of hardware and software has been used for less than one year we already have a
positive feedback from the end-user. Especially have been mentioned: | |||
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- Simple handling due to an intuitive prompting within the user interface and touchscreen
- Low installation requirements and costs due to a compact hardware - Reduced maintenace requirements due to maintenace free housings (no blower) and a decentralized FTP access to parameter - No need to walk to the installation in order to get/view log files. - Status display of relevant informations by HTTP - Elimination of production stops due to early messaging of alert conditions via SMTP and SNMP - Improved protection of the investment due to a powerful hardware-monitoring. | |||
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The positive experiences gathered in Mexico have lead to winning the competition for another automotive project in Shanghai (PRC).
In the first phase already six installations based upon the PPC 5315 are now productive. One main citeria for winning the competition was the
presence of Phoenix Contact in China, because onyl due to this a satisfying support and service can be guaranteed. | |||
| Authors: Dipl.-Ing. Kai Fechner and Dipl-Ing. Oliver Kirsch are members of the department Sales Automotive Group of Phoenix
Contact GmbH & Co. KG, Blomberg.
Dieter W. Kuske is the CEO of I.C.S. Industrielle Automatisierungssysteme GmbH, Lehre. Internet : www.phoenixcontact.de | Knz : 22988 | ||
