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Allen Bradley Guard PLC Driver for DeltaV Programmable Serial Interface Card

1 INTRODUCTION

1.1 Scope

This document is the User Manual for the Allen Bradley Guard PLC serial communication driver firmware for the Emerson DeltaV Control System; it
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Structured Text(ST) Programming Guide MELSEQ PLC

This guidebook is a commentary written for those who will use the GX Developer version 8 software package (hereafter abbreviated to GX Developer)

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S7-200 Tip : Using a Hayes Modem

Special Hardware Requirements:

  • One PC/PPI cable
  • One appropriate interface (depends on the outputs of the modem: for example, a 9-pin male to 25-pin male)
  • One null modem for swapping the transmit and receive lines (lines 2 and 3)
  • One Hayes modem
    The Hayes modem should have a transmission rate of 9600 baud. However, you can use a slower modem.
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S7-200 Tip : Using AS-Interface Data

Special Hardware Requirements:  
Within the scope of the indicated sample system, the following actuator-sensor interface (AS-i) components are used:

  • For a minimum configuration, at least the components listed under item 1 to item 4 are needed. These components may also be connected with a single round cable.
  • The interface modules as well as the control device SIGNUM are connected by means of the AS-interface profile cable.
  • The addressing device is used for setting the slave address.

The slave addresses listed below are used for the sample system. The factory setting for the slaves address is 0. For operation, it has to be set to a value between 1 and 31.

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PLC Communications in a process control system

Communication has become a major part of any process control automation system. Today PLC communication is as much for data acquisition as plant control. The first thing the designer often asks is 'how'? But shouldn't he first be asking 'why'?

Before one can consider how to implement a communication system, one has to consider what the final objective is. What is the importance of the data, what is the amount or volume of data to be transferred and when or how often is the data required. All of these are factors of why the communication is needed. Once all this information is known, one is much better placed to decide how this is to be done.

In order to make this final decision however, we first need to look at the options.
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S7-200 Tips : Using S7-300 as a Master

Special Hardware Requirements:

  • One S7-200 CPU with a EM277 DP Module
  • One S7-300 PLC, consisting of a PS 307 2A power supply unit, a CPU 315-2 DP, and an SM 374 digital input/output simulator module
  • One PC/PPI cable for programming the S7-200
  • One PROFIBUS cable (The cable should be terminated on both ends by means of the matching resistor integrated in the connector. The switch on each connector should be in the ON position.)
  • One MPI cable for programming the S7-300
  • One PC with MPI card (and the STEP 7 programming software, Version 3.1, as well as STEP 7-Micro/WIN Version 2.0)
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S7-200 Tips : Using RS-485 Encoder

Special Hardware Requirements:   
There are two types of encoders, each having different resolutions:

  • Encoder with 13 bit resolution: Type SVE10-06213
  • Encoder with 25 bit resolution: Type SHE86-10214

Manufacturer: Hohner Electrical Engineering, D-78532 Tuttlingen/Germany

It is theoretically possible to connect 8 encoders to an RS 485 interface.

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S7-200 Tips : PROFIBUS/EM 272 Notes

Special Hardware Requirements:

  • One SIMATIC S7-200 CPU 222, CPU 224, CPU 226, or CPU 226XM
  • One EM 277 PROFIBUS DP expansion module

The S7-200 CPUs can be connected to a PROFIBUS DP network by using an EM 277 PROFIBUS DP expansion module. PROFIBUS stands for “Process Field Bus.” DP stands for “distributed peripherals,” that is, remote I/O. The EM 277 allows the S7-200 CPUs to be DP slave devices on a DP network. A DP master can write data to and read data from the S7-200 CPU over the DP network by using the EM 277 PROFIBUS DP module.

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S7-200 Tips : Using Parallel Printer

Special Hardware Requirements:

  • One PC/PPI cable
  • One converter, 9-pin female to 25-pin male
  • One converter, serial-to-parallel
  • One null modem adapter for swapping lines 2 and 3 (if required)
  • One parallel printer
NOTE: 
One problem might occur. Because the SIMATIC S7-200 and the printer both behave as slaves (data communications equipment, or DCE), the data transfer of each device tries to run in the same direction. This means that both the receive and transmit data lines end up connected to each other (lines 2 and 3). You can avoid this problem by setting up the converter properly or by using an appropriate wiring adapter (a null modem adapter).
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OMRON PLC Beginner Guide

In general a Control System is a collection of electronic devices and equipment which are in place to ensure the stability, accuracy and smooth transition of process or a manufacturing activity. It takes any form and varies from power plant to a semi-conductor machine. As a result of rapid advancement of technology, complicated control tasks accomplished with a highly automated control system, which may be in the form of Programmable Logic Controller (PLC) & possibily a host computer, etc. Besides signal interfacing to the field devices ( such as operator panel, motors, sensors, switches, solenoid valve and etc.), capabilities in network communication enable a big scale implementation and process co-ordination besides providing greater flexibility in realizing distributed control system. Every single component in a control system plays an importnat role regardless of size. For instance, as shown in Fig 1.1. the PLC would not know the happenings around it without any sensing devices. And if necessary, an area host computer has to be in place to co-ordinate the activities in a specific area at the shopfloor.

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