What is Telemetry 29-07-08

Telemetry or

Management of Regional Water Supply Schemes with

Information Technology

Assistant Executive Engineer, TWAD Board Maintenance Sub division (Pillur), Coimbatore.

Status of WATER Supply Sector

• Depleting local sources.• Difficult to get individual sources for each habitation.

• Standard of living and public preferences have increased

• People desire to have better quality and quantity of water

Existing maintenance situation:Existing maintenance situation:

• The systems are operated manually

• In each of the schemes no single individual is aware of all the operating parameters of the whole system

• No data on flow, pressure, level and other ground conditions.

• No one knows at what level the systems are operating

• The systems are not operating at their design level/capacity

Existing Scenario ….. (Contd.)

• Upstream beneficiaries grab a major share

of water depriving the legitimate share of

farther and downstream beneficiaries.

Existing Scenario ….. (Contd.)

• Stringent water allocation at design stage

have made the systems rigid and not

amenable to adjust themselves to suit

subsequent demographic changes.

Existing Scenario … (Contd.)

• No on-line data to verify complaints of non-

supply or excess drawl.

• Maintenance engineer is unable to respond to the day to day problems efficiently.

• Any breakdown in the system comes to notice of the maintenance engineer only when reported by the staff or on receipt of complaints of non-supply.

Maintenance Scenario … (Contd.)

• Intermittent operation of the system increases the risk of pollution due to intrusion of external water in to the system during non-supply hours.

• There is scope for improving the performance of all the water supply installations and their optimum utilisation.

SCADA System for Water Distribution

What is the solution:

• The science and technology of automatic measurement and transmission of data by wire, radio, or other means from remote sources

What Is Telemetry

Remote Measurement

•Supervisory control and data acquisition.

•SCADA is confined to one station.

•Telemetry can cover more than one station.

Telemetry Vs SCADA

• The data from each station may be parameters such as pressure, level, flow, Voltage, Frequency, Ampere

• These data are transmitted to another location through a medium such as cable, telephone or radio.

• In Telemetry Control may be Automatic or manual

Components of SCADA System

• SCADA system consist of the following:

1. Field instrumentation

2. Remote stations

3. Communications network

4. Central monitoring station

Field Instrumentation

• Field instrumentation refers to the sensors and actuators that are directly interfaced to the plant or equipment.

• They generate the analogue and digital signals that will be monitored by the remote station.

What is a Hydrostatic level sensor?                                                      

A hydrostatic level sensor is used to measure the pressure created by a liquid. The greater the height of the liquid, the greater the pressure.The pressure creates movement of a flexible piece of metal or ceramic, known as a diaphragm, a bit like a drum, and the position of the diaphragm is measured and a signal is produced that relates to the level of liquid in the tank.As a hydrostatic sensor needs to be in contact with the product and hence has to be corrosion resistant

Ultrasonic sensors use sound waves to measure distance. A sensor would normally be mounted at the top of a tank and direct a sound wave down towards the surface of the product. When the sound wave hits the product it is reflected and returned to the sensor. The sensors calculate this time interval and give a signal proportional to the distance. Ultrasonic sensors are not suitable for use in all applications. If there is foam on the surface then the sound wave will be scattered and the sensor will not receive a signal that it is able to process accurately.

What is an Ultrasonic level sensor?

Ultrasonic Flow Meter

Insertion Type Electromagnetic Flowmeter

Orifice plate with Diff. Pressure Transmitter for Flow measurement

Back

Remote Terminal Unit• The remote station is installed at

the remote plant or equipment being monitored and controlled by the central host computer.

• This can be a remote terminal unit (RTU) or a programmable logic controller (PLC).

Back

Remote Terminal Unit with PSTN modem

Communication Network

• The communications network is the medium for transferring

information from one location to another.

• This can be via telephone line, radio or cable.

What is GSM?

                                                             GSM stands for Global System for Mobile Communications, which is basically the mobile phone network as we know it.It supports not just voice communications but also text messaging and data transfer.

GSM now provides a viable cost alternative to traditional 'land-lines'

What is PSTN?

Public switched telephone network. Basically the normal phone network, or land line.

Back

V-sat terminal

Antenna Tower

Central Monitoring Station•The central monitoring station (CMS) refers to the location of the master or host computer.

•It uses a man machine interface (MMI) program to monitor various types data needed for the operation.

What is SCADA?SCADA stands for Supervisory Control And Data Acquisition. So what does this mean?

Essentially SCADA is a software package designed to display information, log data and show alarms. This can be graphical and tabular formats, words or pictures.

SCADA is used in many industrial processes. The size of a SCADA system can vary greatly.

SCADA can be used to monitor and control plant or equipment. The control may be automatic, or initiated by operator commands.

                                                            .

COIMBATORE COIMBATORE THE MANCHESTER OF SOUTH INDIATHE MANCHESTER OF SOUTH INDIA

REGIONAL WATER SUPPLY SCHEMEREGIONAL WATER SUPPLY SCHEME

A SUCCESSFULA SUCCESSFUL

COIMBATORE WATER SUPPLY SCHEMECOIMBATORE WATER SUPPLY SCHEMEWITH PILLUR AS SOURCE - WITH PILLUR AS SOURCE -

ALREADY BLESSED WITH ALREADY BLESSED WITH SIRUVANI WATERSIRUVANI WATER

ADDS ONE MORE FEATHER TO ITS ADDS ONE MORE FEATHER TO ITS CAPCAP

• No. OF WATER TANKS & CAPACITY - Over 620

(10000lit to lakh lit) 30

• GENERAL LEVEL OF PROJECT AREA - Varies from

150m to 700m

• CAPACITY OF BOOSTER PUMPS - Varies from

1 HP to 100 HP

COMBINED WATER SUPPLY SCHEME TO COIMBATORE LOCAL PLANNING AND RURAL AREAS WITH PILLUR RESERVOIR AS SOURCE

DEMAND, COLLECTION AND MAINTENANCE EXPENDITURE DURING THE YEAR 2000-01TO 2006-07

(RUPEES IN LAKHS)

1246.45

1441.95

1722.15

2020.73 2066.852207.86

2339.02

1912.591867.921840.92

1626.541685.41

797.55

1040.65 1049.96980.55

844.63692.64

974.44 946.48 927.64

0

500

1000

1500

2000

2500

2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07

DEMAND COLLECTION EXPENDITURE

Present usage of Telemetry system

Pressure along pipeline at strategic locations is continuously monitored and any change in pressure pattern is analysed for probable cause.

Valve at Karattumedu (requiring frequent operation) is remotely done from the Master Control Centre/

Transparency of level, flow, pump on/off status and pressure data ensures informed decisions by the maintenance persons.

Power disruptions at various pump houses are monitored from the Master Control Centre.

Pump On/Off status is available in the SCADA screen

Case Study - 1 Identification of leak

On 15.11.07, Reduction in water flow at MSR and BSR was felt. On analysis of SCADA screen a drop in pressure at 8.00 am at Veerapandi pirivu (LS17221) was noted. The field staff sent on reconnaissance reported a leak at LS 23620 of the CWTM. Pumping was stopped at 3.05 p.m. After attending the leak pumping commenced again 3.40 am on 16-11-07.

Case Study – 2 - Identification of leak On19.11.07,Water level in

BSR was depleting fast. On a review of SCADA screen a simultaneous pressure drop at BSR outlet and Singanallur at 11.30 AM was noticed. The field staff sent on reconnaissance reported a leak between BSR and Singanallur. Further investigations revealed an earthmover has damaged an air pipe at LS 40000 of CWTM at 11.30 am The leak has since been attended.

Case Study –3 - Monitoring of intermittent flow

Supply to the Military Defence Establishment at Madukkarai is given for 2 hours daily in the morning. From the trend curve at Madukkarai, a pressure drop from 4.48 am to 6.48 am (Actual supply hours) could be seen.

Case Study - 4 - Monitoring of Power interruptions at pump houses

In the adjoining screens sudden drop in pressure in the pump delivery side at 6.35 am and surge again at 7.09 am indicates stopping of pumping. Actual hours of pumping at each pumping station could be easily monitored.

Thank you