2 Yagur st., Haifa,
ISRAEL 32626
Phone: 972-4-8225060
Fax: 972-4-8234258
E-mail: afsk2323@netvision.net.il
   |
The sustem elements. The basic building block of the SCADA system is the RTU (Remote Terminal Unit) or PLC (Programmable Logic Controller) located near the controlled object. The controller performs data acquisition, control logic and command assignment to the relevant field equipment. Depending on the amount of data the controller may be equipped with any number of input / output modules. All RTU's within a system exchange data with the Central Control Room by means of telephone or cable line through a MODEM device or via wireless RADIO. For systems engaged in transportation of products through pipelines laid in sparsely populated or uninhabited areas with limited access, radio communi-cation between the objects is the major, if not the unique way of data transfer. The Central Control Room computers are equipped to communicate both through cable and radio. Data is processed according to algorithms and presented upon graphic displays of the process. An operator's working place comprises a monitor (CRT), a keyboard and a "mouse" enabling him to perform any kind of operation along the technological line subject to the software. An operator may call any specific part of the on-going technological process to the HMI screen, perform necessary switching, modify the system's properties as well as monitor all parameters. SCADA system, being totally computerized, permits an operator to follow and analyze all possible changes within a system. All parameters are presented as on-screen graphics with a real-time change history. The system registers the entire activity of the Central Control Room operator, as well as the local operators on-site. SCADA is a bi-directional system of communication, providing for simultaneous reception of relevant data from an object and transmission of commands. |
