Scada

3/10/2009

PANEL DE CONTROL USANDO 4-20MA O VOLTAJE

FUNDAMENTOS DE SISTEMAS SCADA
Universidad de la salle Docente: Ing. Efrain Bernal

Programa de Ingeniería de Diseño y Automatización Electrónica Sistemas de control remoto en automatización

ADVANTAGES
•It is simple, no CPUs, RAM, ROM or software programming needed •The sensors are connected directly to the meters, switches and lightson the panel •It could be (in most circumstances) easy and cheap to add a simple device like a switch or indicator

DISADVANTAGES
•The amount of wire becomes unmanageable after the installation of hundreds of sensors •The quantity and type of data is minimal and rudimentary •Installation of additional sensors progressively harder as the system grows becomes

•Re-configuration of the systembecomes extremely difficult

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•Simulation using real data is not possible •Storage of data is minimal and difficult to manage •No off-site monitoring of data or alarms •Someone has to watch the dials and meters 24 hours a day

SCADA REFERS TO THE COMBINATION
OF TELEMETRY AND DATA ACQUISITION.

SCADA (Supervisory Control and Data Acquisition)
A system where by computers areused to collect real-time data from plant machinery to provide central monitoring, control and process visualization of the plant and its facilities. Plant instrumentation (sensors, switches, motors, pumps, valves etc.) is connected to the PLC, which in turn is connected to the PC running the SCADA software.

PC TO PLC OR DCS
WITH A PLANT BUS AND SENSORS

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ADVANTAGES OF THEPLC/DCS SCADA
•The computer can record and store a very large amount
of data •The data can be displayed in any way the user requires •Thousands of sensors over a wide area can be connected to the system •The operator can incorporate p p simulations into the system real data

•Many types of data can be collected from the RTUs •The data can be viewed from anywhere, not just on siteDISADVANTAGES
•The system is more complicated than the sensor to panel type •Different operating skills are required, such as system analysts and programmer •With thousands of sensors there is still a lot of wire to deal. •The operator can see only as far as the PLC

IEDS (INTELLIGENTELECTRONIC DEVICES).

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THE ADVANTAGES OF THE PC TO IED FIELDBUS SYSTEM
•Minimal wiring is needed•The operator can see down to the sensor level •The data received from the device can include information like…serial numbers, like… model numbers, when it was installed and by whom y •All devices are plug and play, so installation and replacement are easy •Smaller devices means less physical space for the data acquisition system

THE DISADVANTAGES OF A PC TO IED SYSTEM
•The more sophisticatedsystem requires better trained employees •Sensor prices are higher (but this is offset somewhat by the lack of PLCs) PLCs) •The IEDs rely more on the communication system system.

COMPARISON OF THE TERMS SCADA, DCS, PLC AND SMART INSTRUMENT IED’S
A SCADA (or supervisory control and data acquisition) system means a system consisting of a number of remote terminal units (or RTUs) collecting field dataconnected back to a master station via a communications system. The master station displays the acquired data and also allows the operator to perform remote control tasks. The accurate and timely data (normally realtime) allows for optimization of the operation of the plant and process. A further benefit is more efficient, reliable and most importantly, safer operations. This all results in alower cost of operation compared to earlier non-automated systems. There is a fair degree of confusion between the definition of SCADA systems and process control system. system.

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SCADA has the connotation of remote or distant operation, because of that, we are considering telecommunications and SCADA essential parts to remote control learning. The inevitable question is how...