Journal of Scientific & Industrial Research 858 Vol. 68, October 2009, pp. 858-860
J SCI IND RES VOL 68 OCTOBER 2009
Remote monitoring system for distributed control of industrial plant process R Kirubashankar1*, K Krishnamurthy1 and J Indra2 1
Department of Mechatronics Engineering, 2Department of Electronics & Instrumentation Engineering, Kongu Engineering College, Perundurai, Erode 638 052, India Received 10 February 2009; revised 17 June 2009; accepted 09 July 2009
This paper proposes a remote monitoring system as part of Distributed Control System (DCS) of process plant. Remote plant critical alarms from DCS are continuously monitored online through Supervisory Control and Data Acquisition (SCADA) system. A report, which contains alarm details formulated through MS-Excel, is sent to respective e-mail recipients through Outlook Express. For system maintenance, M2M gateway and Virtual Private Network (VPN) technology are used in remote monitoring. Service engineers can remotely view real time conditions of plant area, diagnose problem and help plant engineers to rectify it to avoid plant failures and maximizing plant process availability. Keywords: Distributed control system, Supervisory control and data acquisition system, Virtual private network
Introduction Remote monitoring and intelligent maintenance is one of the most important criteria for maximizing production and process plant availability1-3. Wireless media has been undergoing a rapid innovation process in search for a reliable, simple and business-viable technology for fast, easy and inexpensive diagnosis of faults in process plants. Majority of industries use distributed control system (DCS) for high reliability, improved response time, improved operator interface to plant, improved accessibility of plant data to engineering & management personals and improved historical storage and retrieval system. This study proposes a remote monitoring system as part of DCS of process plant. Existing Process Control Systems Distributed Control System (DCS)
DCS collects data from process plant for formulating advanced process control strategies (Fig. 1). Supervisory Control And Data Acquisition (SCADA) System
SCADA system is a software package positioned on top of hardware. It is interfaced with industrial processing units through Programmable Logic Controllers (PLCs). It is not always possible and feasible *Author for correspondence Tel: 04294-226725 E-mail:
[email protected];
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to monitor industrial processing units physically in extreme environmental conditions of plant. This leads to improper maintenance causing breakdown. This delay in identifying causes of failure renders industrial units unusable. Such problems can be solved by constantly monitoring the plant and environmental conditions from a remote location. General Packet Radio Service (GPRS) System
GPRS remote monitoring device enables industrial units to be monitored through wireless Internet from a remote location. GPRS provides actual packet radio access to Global System for Mobile (GSM) communication and Time-Division Multiple Access (TDMA) users. Main benefits of GPRS are to reserve radio resources when there is data to send and it reduces reliance on traditional circuit-switched network elements. Increased functionality of GPRS decreases incremental cost to provide data services among consumer and business users, with reliability, response time, and other supported features. Proposed Remote Monitoring System for Distributed Control (RMSDC) Proposed RMSDC (Fig. 2) is a part of DCS of process plant. In any industrial plant running with DCS, following parameters of DCS are monitored continuously: i) alarm (process alarms, critical alarms etc.) monitoring; ii) mimic /graphic display; iii) trend display; iv) operator guidance display; v) system & diagnostic display; vi) control; vii) bar chart; viii) sequence display; and ix) fault analysis display.
KIRUBASHANKAR et al: REMOTE MONITORING FOR DISTRIBUTED CONTROL OF PROCESS PLANT
Fig. 1— Architecture of DCS
Fig. 2— Architecture of proposed remote monitoring system for distributed control of industrial process plant
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Alarms are used in any plant for ensuring fault free operation. A separate database is made in MS Access / MY SQL in SCADA for maintaining alarm code, date and time of occurrence of alarm, alarm description, alarm meaning, alarm cause and action. Whenever an alarm event concerning alarm occurs in plant, SCADA scans alarm code in DCS alarm information file. Alarm code is then compared with database and alarm report file is generated in MS Excel. Each alarm report consists of alarm description, alarm meaning, alarm cause, action etc., besides information about alarms that occurred 30 minutes earlier. It sharpens diagnostic procedure to identify causes of faults. A SCADA- VB (Visual Basic) application is created for transferring generated alarm report automatically to MS outlook express, which is configured with customer user ID. It takes GPRS radio communication and Internet technology to communicate between remote monitoring computer and field monitoring computer4. M2M gateway is used to built wireless GPRS networks running independent of mobile operators. It issues virtual static IP addresses for remote field devices and sites. Alarm report is transmitted to GPRS network using M2M gateway. GPRS network connects Internet. Whenever, connection is established, report from outlook express is forwarded to Global response centre / Customer Service Department. Forwarded information contains all details pertaining to plant operation alarms. Through Virtual Private Network (VPN) service5, engineers can view real time conditions of affected plant area and diagnose problem remotely for providing solution measures to
plant engineers. Proposed system was successfully implemented in process control area of a leading MNC. Conclusions Industrial process plant can be monitored remotely by proposed system architecture having GPRS and wireless Internet connection in conjunction with DCSSCADA. It improves reliability, response time, plant interface under continuous remote real time monitoring under adverse environmental conditions of process plants for maximizing plant operational conditions. Acknowledgements Protocol Automation Technology, Bangalore, India, financially supported this project. Authors thank all project partners for meaningful discussions. References 1
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Li H-Y, Web-based remote monitoring and control for process plants, in Proc of Int Conf on Machine Learning & Cybernetics, 2005 936-941. Kubo M & Ikeda H, New Remote Maintenance System (RMS) for Distributed Control System, in SICE-ICASE Int Joint Conf, 8, TP27-53/I59/(2006). Oltean S E, Abrudean M & Dulau M, Remote monitor and control application for thermal processes using TCP/IP, in IEEE Int Conf on Automation, Quality & Testing Robotics, (IEEE, USA) 25-28 May 2006, 209-213. Rotharmel S, IP based telecom power system monitoring solution in GPRS networks, in Int Conf on Telecom Energy, INTELEC 2007, 2007, 769-774. Venkateswaran R, Virtual Private Networks, IEEE Potentials (Lucent Technol. Bell Lab., USA) 2001, 11-15.
