UPPCL Project

7/27/2019 UPPCL Project

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UTTAR PRADESH POWER CORPORATION

LIMITED, LUCKNOW

ABOUT UPPCL

Uttar Pradesh Power Corporation Limited uses microwave communication system for

transmitting and receiving data at its SLDC located at Shakti Bhawan in Lucknow.

U.P. Power Corporation Limited, incorporated under the companies Act 1956, was

incorporated in 2004 with the main objective to acquire, establish, construct, take over, erect,

lay, operate, run, manage, hire, lease, buy, sell, maintain, enlarge, alter, renovate, modernize,

work and use electrical transmission lines and/ or network through extra high voltage, high

voltage and associated sub-stations, cables, wires, connected with transmission ancillary

services, telecommunication and telemetering equipment in the State of Uttar Pradesh, India

and elsewhere.

Uttar Pradesh Power Transmission Corporation Ltd. (UPPTCL) has a very large network of

high voltage transmission lines in whole UP (about 24,000Km). Transmission lines transfer power from power houses to substations and from one substation to many other substations or



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vice versa. Power is generated at low Voltage (of the order of 3.3KV to 25KV) and is

stepped-up to high voltage (765KV, 400KV, 220KV & 132KV) for evacuating power into

the grid network through transmission lines.

33/11KV Substations of distribution companies (DISCOMs) draw power from transmission

substations through 33KV lines and distribute that to consumers (at 0.4KV, 11KV or in few

cases at 33KV). Distribution companies have industrial, rural and domestic load, which

varies from time to time of the day and from season to season of the year. Sometimes, large

variations in load cause over/under loading of lines, transformers or generators. Variations

beyond limits and breakdowns cause fluctuations in voltages & grid frequency of the

network. Control Centers, in hierarchical form, are set up for smooth functioning of the grid.

Each generating unit or substation has its own Control Centre. These are also named as Unit

Control Board (UCB)/Main Control Board (MCB)/Control Room. These Control Centres

report to Area Load Dispatch Station (ALDS). ALDS report to Central Load Dispatch Station

(CLDS at State Level), CLDS reports to Regional System Coordination & Control Centre(RSCC at regional level having a group of States and Central sector units of that region) &

finally on top is National Load Dispatch Centre (NLDC) which is being set-up.

These control centers need real time information about generation, power flow, voltage,

frequency, etc. of generators & substations. This information is exchanged in data or voice

form. For exchange of such information, a reliable and dedicated communication system is

required. Substations or power houses, situated at both ends of transmission line, need

information in voice form. Trip commands (also called protection signal) are transmitted

from one substation to the other substation, through transmission line. When 'earth' or 'over-current' fault is sensed by one end of the transmission line, a trip command is generated,

which travels through communication system and opens circuit breaker (switchgear) of the

other end. Dedicated communication system is required for transmission of protection signal.



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COMMUNICATION SYSTEM

Communication is process of transmission of information from one place to another. The

place from which information is send is called source and the place to which information

goes is called destination.

The information can be in form of a sound signal like speech or music, or it can be in the

form of pictures (TV Signals) or it can be data information coming from a computer.

The block diagram of simplest possible communication system:

Noise, which is unwanted signal is added when signal passes through communication

medium.

The communication medium can be conducting wires, cables, optical fibers or free space.

Types of communication system

Depending upon types of communication medium communication system can be divided into

following parts:

a) Line communication

b) Radio / microwave communication

c) Optical communication (basically a line communication system)

Line Communication

The line communication system use communication mediums like the simple wires or

cables.

Due to physical connection from one point to the other, these systems cannot be used for

the communication over long distances.

The example of such systems are telegraph and telephone systems , cable T.V. etc.

Microwave Communication

Microwave or Radio communication systems use the free space as their communication

medium. They do not need wires for sending the information from one place to another.

These sytems transmit the signal using a transmitting antenna in the free space. The

transmitted signal is in the form of electromagnetic waves. A receiving antenna will pick

up this signal and feed it to the receiver.



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Radio communication can be used for long distance communication. The examples are

radio or T.V. broadcasting ,Satellite communication etc.

Optical communication

In this type of communication system optical fibers are used as transmission medium. In

optical fiber information does not degrade because of no presence of noise.

Light is launched into the fiber using a light source such as LED or Laser. It is detected on

the other side using a photo detector such as phototransistor.

Optical fibers have higher bandwidth therefore can operate at higher data rates. They are

high immune to electromagnetic interferences. They are small in size and of light weight,

used for point to point communication.

Optical fibers are now used in telephone systems and in local area networks (LANs).

Power System Communication

History of Power System Communication

In mid sixties, in erstwhile U.P. State Electricity Board(UPSEB), even P&T lines were not

available for communicating messages among substations and powerhouses . In some

cases, telex messages were being sent through P&T department between few control

centers situated in major cities.

Later on, Power Line Carrier Communication (PLCC) systems were used for voice

communication among substations, powerhouses, grid control centers and for sending

protection signals.

In late seventies, sub-VF band of few PLCC links were used for transmitting tele-metering

signal (containing data of power flow, voltage, frequency, circuit breakers/ isolator status,

etc.) to control centers.

Thereafter in eighties, microwave communication system was introduced and 38 nos.

microwave stations were set up in Uttar Pradesh, STARTING FROM Rishikesh in the

north-west to Rihand in the south-east. It was an analogue communication system.

Load Dispatch Centers

After modernization & computerization of control centers, the nomenclatures of control

centers have been changed. A hierarchy of control centers have been formed.

The basic control center, ALDS of every state has been named as sub-Load dispatch

Centre (sun-LDC)

CLDS has been named as State Load dispatch Centr e (SLDC)

Regional System Coordination & control centers (RSCC) of northern region at New Delhi

has been named as Nor thern Regional Load Di spatch centr e (NRLDC)



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In the above Fig. National Load Dispatch Centre (NLDC) has been shown at the top. Its

control center is in construction stage at New Delhi and will be operational by the time all

India grids are combined. Below this, five nos. regional level Load Dispatch Centers have

been shown. Presently, except for southern region, grids of all other regions areinterconnected and are running in combined form. This way, Northern Regional Load

Dispatch Centre (NRLDC) Is now part of All India Grid or say „ National Grid’ .

The role of the NRLDC is to monitor and supervise the grid and power generation of the

region. It focuses attention on the regional interconnected network. By using „Energy

Management System‟ (EMS) and advanced application programs, NRLDC coordinates

with all inter-region and inter-state power exchange.

Below NRLDC, State level SLDCs and Central Project Coordination & Control Centre

(CPCC) have been shown.

The primary role of SLDCs is to monitor, Control and coordinate the generation,transmission and distribution of power within the state while ensuring safety and

continuity of its transmission and sub-transmission power networks. CPCC (North)

coordinates with all central sector projects of northern region such as thos of NTPC,

NHPC, Power grid, Tehri, etc. CPCC gets data from central sector projects and the data is

added at regional level.

Direct data transmission does not take place between SLDC of one state with SLDC of

another State.



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Uttar Pradesh SLDC

SLDC of Uttar Pradesh is situated at 5 th Floor of Shakti Bhawan, Lucknow. This SLDC

has the ability to exchange data with NRLDC, New Delhi and its sub-LDCs. Under it,there are five sub-LDCs.

Each sub-LDC collects datafrom various „Remote terminal Units‟ (RTUs), installed at

important sub-stations(400KV, 220KV, and few 132KV) and powerhouses. So far in

UPPTCL, 72 RTUs have already been integrated with the system.

Each RTU automatically pcks up required information (MW, KV, Hz, Circuit Breaker &

isolator status) of the Sub- Station / powerhouse and transmit it to its sub-LDC through

communication system. This information is processed in the data server of sub-LDC.

Data in the form of binary stream of pulses are sent by RTU at the speed of 300,600 or

1200 bits per second rate(baud). At sub-LDC, the information is updated within 10 sc.

Work of these control centers is dependent upon SCADA (Supervisory Control and Data

Acquisition) system and various types of communication systems.

Transmission of Data

From substation to sub-LDC

Below in Figure, main equipment from substation/power house to its sub-LDC has been

shown in a very simple form.

Transmission of Data from substation/Power house to subLDC

Current Transformers (CTs) and Potential Transformers (PTs), installed on transmission

lines, provide inputs to transducers of SIC (Supervisory Interface & Control) & RTU

(Remote Terminal Unit) panel.

The output of RTU is connected to the communication equipment, through Modem. In

between substation & sub-LDC, a communication link has been shown.

Modem output at receive side is connected with the CFE (Communication End Frame).

Its output is connected with data server. In practice, dual servers are provided so that if

one server fails then second server takes over.



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Each RTU is automatically polled by Server of sub-LDC to obtain each data of that RTU

in a cyclic form.

System Software is arranged in such a way that each data repeats at least once in 10 sec

and is stored in the database of sub-LDC. This data is processed in database formats and

is retrieved for different applications. These formats or graphics are displayed or printedas per requirement.

At subLDC, System Control Officers use this data to monitor and analyze position of the

grid.

From sub-LDC to SLDC, Lucknow

Below in Figure , main equipment from subLDC to SLDC, Lucknow has been shown in a

very simple form.

A systematically combined/processed data of all RTUs, in server of subLDC, is

transmitted to SLDC Lucknow.

This data in the form of 64Kb/s signal is sent through multiple paths/channels. Presently

four channels are used. For this purpose 'Routers' are used. Routers basically work as

modem but is has multiple paths for LAN, WAN or internet, etc.

In UPPTCL, for transmission of data, from subLDC to SLDC, only wideband

communication system (microwave or fibre-optic links) is being used.

In SLDC, data from all other subLDCs is also received simultaneously and are processedfor different purposes and applications.

From Inter-Control Centre Communications Protocol (ICCP) Servers of SLDC, complete

data of all subLDCs is sent to NRLDC, New Delhi through wideband communication

system.

COMMUNICATION FOR POWER SYSTEM

Following are mainly three inter-related areas of functions in UPPTCL for management

of power system:

a)

Telecommunication b) SCADA- Supervisory Control And Data Acquisition System



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c) EMS – Energy Management System

A. TELECOMMUNICATION

There are three different types of telecommunication systems in UPPTCL i.e.

i. Microwave Communication System,

ii. Fibre -optic Communication System,

iii. PLCC-Power Line Carrier Communication.

Voice Frequency (VF) channels of all these systems have been integrated/interconnected

to make a hybrid communication system.

Microwave & Fibre Optic are multi-channels communication systems and are also called

'Wideband communication system'. PLCC is single channel communication system.

A brief overview of these three types of telecommunication system of UPPTCL is as

below:

Microwave Communication System

Microwaves travel in 'Space' and any object in the path can obstruct communication

system. Microwave is called 'line-of-sight' communication

system. As such, its antennas are mounted on high towers so

that even trees should not obstruct path of microwaves. UPPTCL is using frequency band between 2.3 GHz to 2.5

GHz. The height for antenna are calculated by taking into

account many factors, such as, distance between two

locations, path clearance, height from sea level of these

locations, tropical area, reflection points, and so on. As such,

height of towers varies from location to location.

Tower heights at our microwave stations range from 30 to 110 meters. Starting from

Muzaffarnagar (220KV substation Nara), in the north-west, to Rihand (Pipri), in south-

east of UP, 33 microwave stations have been established. This covers a route length of

over 1000 Km.

In present digital microwave system, Transmitters & Receivers of 'Normal' and 'Standby'

equipment has got same frequency and is called 'hot standby' system.

Only one column is connected with the antenna.

Microwaves are susceptible to 'fading phenomenon' due to change in

atmospheric medium above the earth, during day & night and from

season to season. Some links, which are suspected for excessive fading

during propagation of signal, have been provided with additional

antennas for 'space diversity'. In space diversity system, Transmitters &

Receivers have additional antennas, located at different heights.



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New digital microwave system has got many useful features for easy maintenance. Its

'Network Management System' (NMS) helps in remote diagnosis operation and

maintenance. As an example, microwave NMS equipment at Lucknow detects defective

circuits between Obra-Pipri and diagnoses its problem.

Microwave equipment is of 'Nokia' Finland make.

Fibre Optic Communication System

It is new communication system and has been introduced in UPPTCL since 2001. Optical

fibre cable, in the form of 'Optical Fibre Composite Ground Wire' (OPGW), has been

installed on transmission towers by replacement of earth wire.

'Optical Line Terminal Equipment' (OLTE) have been manufactured by Fujitsu, Japan

and have been installed at eight sub-stations (Muradnagar, Moradabad, C.B.Ganj, Unnao,

Panki, Sahupuri, Sarnath & Azamgarh).

The electrical signal of 2Mb/s or 34Mb/s, as the case may be, from OLTE is connected

with Primary Multiplexing equipment supplied by 'Nokia' Finland. Its NMS provides

operational support for the 'Fibre Optic Transmission System' (FOTS).

For testing, commissioning & maintenance 'FLEXR' and 'FLEXR Plus' computer

software programmes have been provided. 'FLEXR' is used for initial settings of OLTEs

of fibre optic network. Similar to microwave NMS, 'FLEXR Plus' helps in remote

diagnosis, operation and maintenance of fibre optic network.

For complete communication control system, a NMS100 system has installed at NRLDC,

New Delhi, which is in position to diagnose faults of whole northern region.

OPGW has been manufactured by Farukawa, Japan. They have done replacement work,

on live (hot) lines, by using a unique installation technology.

The OPGW in our system has got twelve (12) 'Dual Window Single Mode' (DWSM) type

fibres in it. Optical signals of 1310 or 1550 nanometer (nm) wavelength are being used.

Only two fibres are required for a multi-channel link between two stations. One fibre is

used for transmitting optical signal and second for receiving from other end.

In our system two fibres have been used for 'Normal' communication path and two fibres

for 'protection' path.

Fibre optic communication system has got a wide bandwidth transmission capability.

Two fibres are sufficient for providing more than one lakh telephone channels on both

sides. As such, a high-speed data, containing large volumes of information can be

transmitted at low cost.

Power Line Carrier Communication System

Power Line Carrier Communication (PLCC) is a single channel communication system in

which its channel (300 to 3400 Hz) is divided into two parts i.e. speech band is generally

kept 300 to 2400Hz or 300 to 2000Hz and rest is used as data band.



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Due to narrow speech band in PLCC, voice of poor quality is available in comparison to

wideband communication system.

In this system, signal travels on the transmission line from one end to other end.

Transmitter output (Radio Frequency signal) is fed to the transmission line through a

Coupling Capacitor or CVT. RF power output is in frequency band from 70 KHz to 500KHz.

Inductors, called 'Wave Traps' are used at the ends of the transmission lines, before

transformers, to pass 50Hz a.c. power but block radio frequency signals.

UPPTCL has a wide network of PLCC links. Presently, its number of PLCC links are

about 550.

SCADA SYSTEM

In SCADA system measured values, i.e. analogue (measured value) data (MW, MVAR,V, Hz Transformer tap position), and Open/Closed status information, i.e. digital data

(Circuit Breakers/Isolators position i.e. on/off status), are transmitted through

telecommunication channels to respective sub-LDCs.

For this purpose Remote Terminal Units (RTUs) at 400KV, 220KV and few important

132KV sub-stations have been installed.

System values & status information below 132 KV have not been picked up for data

transmission, except for 33KV Bus isolator position and LV side of generators.

Secondary side of Current Transformers (CT) and Potential Transformer (PT) are

connected with 'Transducers'. The output of transducers is available in dc current form (inthe range of 4mA to 20mA).

Analogue to digital converter converts this current into binary pulses. Different inputs are

interleaved in a sequential form and are fed into the CPU of the RTU. The output of RTU,

containing information in the form of digital pulses, is sent to subLDC through

communication links.

Depending upon the type of communication link, the output of RTU is connected, directly

or through Modem, with the communication equipment. At subLDC end, data received

from RTU is fed into the data servers.

In general, a SCADA system consists of a database, displays and supporting programmes.In UPPTCL, subLDCs use all major functional areas of SCADA except the 'Supervisory

Control/Command' function.

The brief overview of major 'functional areas' of SCADA system is as below:

1. Communications - Sub-LDC's computer communicates with all RTU stations under its

control, through a communication system. RTU polling, message formatting, polynomial

checking and message retransmission on failure are the activities of 'Communications'

functional area.



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2. Data Processing - After receipt of data through communication system it is processed.

Data process function has three sub-functions i.e. (i) Measurements, (ii) Counters and

(iii) Indications.

' Measurements' retrieved from a RTU are converted to engineering units and

linearised, if necessary. The measurement are then placed in database and are checkedagainst various limits which if exceeded generate high or low limit alarms.

The system has been set-up to collect 'Counters' at regular intervals: typically 5 or 10

minutes. At the end of the hour the units is transferred into appropriate hour slot in a

24-hour archive/history.

' Indications' are associated with status changes and protection. For those statuses that

are not classified as 'alarms', logs the change on the appropriate printer and also enter

it into a cyclic event list. For those statuses, which are defined as an 'alarms' and the

indication goes into alarm, an entry is made into the appropriate alarm list, as well as

in the event list and an audible alarm is generated in the sub-LDC.

3. Alarm/Event Logging - The alarm and event logging facilities are used by SCADA data

processing system. Alarms are grouped into different categories and are given different

priorities. Quality codes are assigned to the recently received data for any 'limit violation'

and 'status changes'. Alarms are acknowledged from single line diagram (or alarm lists)

on display terminal in LDCs.

4. Manual Entry - There is a provision of manual entry of measured values, counters and

indications for the important sub-station/powerhouse, which are uncovered by an RTU

or some problem is going on in its RTU, equipment, communication path, etc.

5. Averaging of Measured Values - As an option, the SCADA system supports averagingof all analogue measurements. Typically, the averaging of measured values over a period

of 15 minutes is stored to provide 24 hours trend.

6. Historical Data Recording (HDR) - The HDR, i.e. 'archive', subsystem maintains a

history of selected system parameters over a period of time. These are sampled at a pre-

selected interval and are placed in historical database. At the end of the day, the data is

saved for later analysis and for report generation.

7. Interactive Database Generation - Facilities have been provided in such a way that an

off-line copy of the SCADA database can be modified allowing the addition of new

RTUs, pickup points and communication channels.

8. Supervisory Control/Remote Command - This function enables the issue of 'remote

control' commands to the sub-station/powerhouse equipment e.g. circuit breaker trip

command. Though, there is provision of this function in this system, yet it is not used in

U.P. As such, related/associated equipment have not been ordered.

9. Fail-over - A 'Fail-over' subsystem is also provided to secure and maintain a database of

devices and their backups. The state of the device is maintained indicating whether it is

'on-line' or 'failed'. There is a 'backup' system, which maintains database on a backup

computer and the system is duplicated.

SLDC Lucknow has a large and active 'Mimic Board' in its Control room. This mimic board displays single line diagram of intra State transmission system i.e. grid network of



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400KV, 220KV and important 132KV sub-stations, transmission lines, thermal & hydro

powerhouses.

Outgoing feeders, shown in the mimic board, have 'achieve' (LED display) colored

indications, of three different colors, to show the range of power flow at any moment i.e.

'Normal', 'Nominal' or 'Maximum' of its line capacity. UPPTCL's transmission network is expanding rapidly and thereby number of RTUs is

also increasing. For new substations and lines, displays in active and passive forms are

required to be made in the Mimic diagram. But, Mimic Board has a limitation that it

cannot incorporate/add large volume of displays for substations/power

houses/transmission lines in 'active' form due to space constraint and congestion. Due to

this Mimic Board is going to be supplemented with a Video Projection System (VPS) at

SLDC, Lucknow in near future. Also in SLDC & subLDCs, displays of single line

diagrams of RTU sub-stations/power house are viewed on VDUs of large size (21").

C) ENERGY MANAGEMENT SYSTEM (EMS)

For energy management of the power system, control personnel and application software

engineers use SCADA data available in the database by using EMS software. The software

functions are based on the Energy Management Platform (EMP). All servers have 'Open

VMS' operating system. All Personal Computers (PCs) have 'Window NT' operating system.

Important features are as below:

1. The Data Base Compiler provides a consistent source of data usable for the applications

in an efficient form. The Data Base Compiler does final checking for completeness andconsistency of the entries for a specific application and prepares those special tables

which are needed for the efficiency of specific application programmes.

2. Recording of 'Sequence of Events' (SOEs) is the most innovative feature provided in this

system. A RTU has the ability to accurately time tag status change and report this

information to sub-LDC. All RTUs in the system are 'time synchronised' with the master

station. Global Positioning System (GPS) system has been used at all subLDCs & SLDC.

In the event of any tripping, sequence of events can be well established on time scale with

a resolution of 10 milliseconds.

3. Normally, 'Automatic Generation Control' (AGC) function issues control commands togenerating plants using the concept of Area Control Error (ARE). It is base on deviations

in 'standard frequency (50 Hz)' and 'scheduled area interchanges' from that of the 'actual

frequency' and 'actual area interchanges'. The scope of AGC function for UPPTCL has

been limited to open loop operation i.e. the software provides the desired corrective

actions for each plant, but the actual command are not issued. It is left to 'System Control

Officer' to take necessary action as divided by AGC Controller. In the event of

unavailability of sufficient generation to satisfy the AGC requirement, the System Control

Officer can enforce required quantum of load shedding.

4. For 'Operation Scheduling' the application software has 'short-term' and 'long-term'

'System Load Forecasting' functions to assist dispatching Engineer/control Officer in

estimating the loads that are expected to exist for one to several days in advance. This



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function provides a scientific and logical way of scheduling of resources in a very

effective manner.

Under 'Short-term Load Forecasting' function, application software engineers are able

to forecast weekly peak demands and load duration curves for several months into the

future.

Under 'Long-Term Load Forecasting' function, forecasting of monthly peak demands

and load duration curves for several years into the future can done for the use of

'Power System Planner'.

5. The other functions like economic dispatch, reserve monitoring, production costing,

inter system transactions scheduling, etc. are available to guide System Control Officer

to optimally use available resources.

6. Power System Control Officer/Analyst would be able to use contingency analysis

function to assess the impact of specified contingencies that would cause line (s)overloads, abnormal voltages, and reactive limit violations.

7. The EMS software system may have many other applications for use, which include

network topology, performing of state estimation, optimal power flow (OPW)

programme, stability programme, power flow displays, help and instructional displays,

tabular displays, single line diagram displays, etc.

Block Diagram For Data And Speech Communication

Communication at Power Corporation is of two types, data communication and speechcommunication. Data is basically voltage, frequency, power, current etc. Speech is data in

voice form.



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RTU (Remote Terminal Unit)

A remote terminal unit (RTU) is a microprocessor-controlled electronic device that

interfaces objects in the physical world to a distributed control system or SCADA

(supervisory control and data acquisition system) by transmitting telemetry data to the

system, and by using messages from the supervisory system to control connected objects

An RTU monitors the field digital and analog parameters and transmits data to the Central

Monitoring Station. An RTU can be interfaced with the Central Station with different

communication media (usually serial (RS232, RS485, RS422) or Ethernet).

RTU can support standard protocols (Modbus, IEC 60870-5-101/103/104, DNP3, IEC

60870-6-ICCP, IEC 61850 etc.) to interface any third party software. An RTU can monitor analog inputs of different types including 4 to 20 milliamperes (4 –

20 mA), 0 –10 V., −2.5 to 2.5 V, 1 – 5 V etc.

Modern RTUs are usually capable of executing simple programs autonomously without

involving the host computers of the DCS or SCADA system to simplify deployment, and

to provide redundancy for safety reasons.

Comparison with other control systems

RTUs differ from programmable logic controllers (PLCs) in that RTUs are more suitable

for wide geographical telemetry, often using wireless communications, while PLCs are

more suitable for local area control (plants, production lines, etc.) where the system

utilizes physical media for control.

The IEC 61131 programming tool is more popular for use with PLCs, while RTUs often

use proprietary programming tools.

RTUs, PLCs and DCS are increasingly beginning to overlap in responsibilities, and many

vendors sell RTUs with PLC-like features and vice versa.

The industry has standardized on the IEC 61131-3 functional block language for creating

programs to run on RTUs and PLCs, although nearly all vendors also offer proprietary

alternatives and associated development environments

http://en.wikipedia.org/wiki/Microprocessor

http://en.wikipedia.org/wiki/Distributed_control_system

http://en.wikipedia.org/wiki/SCADA

http://en.wikipedia.org/wiki/Telemetry

http://en.wikipedia.org/wiki/RS232



http://en.wikipedia.org/wiki/Ethernet

http://en.wikipedia.org/wiki/Modbus

http://en.wikipedia.org/wiki/IEC_60870-5

http://en.wikipedia.org/wiki/DNP3



http://en.wikipedia.org/wiki/IEC_61850

http://en.wikipedia.org/wiki/Milliampere

http://en.wikipedia.org/wiki/Current_loop#Analog





http://en.wikipedia.org/wiki/Programmable_logic_controller














http://en.wikipedia.org/wiki/Milliampere




http://en.wikipedia.org/wiki/DNP3


http://en.wikipedia.org/wiki/Modbus

http://en.wikipedia.org/wiki/Ethernet




http://en.wikipedia.org/wiki/Telemetry



http://en.wikipedia.org/wiki/Microprocessor



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Some suppliers of RTUs have created simple graphical user interfaces GUI to enable

customers to configure their RTUs easily. Some examples are MoxGRAF from MOX

Products for their MX602 Field Controller and PC-Link from Promosys Technology for

their RTU-1, RTU-3 and RTU-8.

Applications

Oil and gas remote instrumentation monitoring, (offshore platforms, onshore oil

wells).

Networks of remote pump stations (wastewater collection, or for water supply).

Hydro-graphic monitoring and control (water supply, reservoirs, sewerage systems).

Environmental monitoring systems (pollution, air quality, emissions monitoring).

Mine site monitoring applications.

Protection supervision and data logging of Power transmission network

Air traffic equipment such as navigation aids (DVOR, DME, ILS and GP)

Outdoor warning sirens, in both controlling them, and sending back data for

verification of activation, trouble with the siren, or other data.

Structure of RTU

The main parts of RTUs are:

The RTUs consist of process module, analog and digital input modules and

communication interface, power supply unit and screw termination on the rear of the panel for field connections.

The various parameters, which are to be acquired, are first taken from the

substation/generating station through current transformer and potential transformer

and brought to the control room in the control panels.

The basic functions of RTU are:

1) Collect power system data.

2) Filter and process the system data

3)

Transmit data to control center

4) Receive the control commands

Remote terminal unit

http://en.wikipedia.org/wiki/GUI

http://www.mox.com.au/


http://www.mypromosys.com/home.html

http://en.wikipedia.org/wiki/Environmental_monitoring

http://en.wikipedia.org/wiki/Environmental_monitoring

http://www.mypromosys.com/home.html



http://en.wikipedia.org/wiki/GUI



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Hardware :

The general arrangement of sub-system inside the RTU panel are:

AIC: Analog input card

DIC: Digital input card

MCB: Miniature circuit breaker

IL: Indicating lamp

The power supply unit is placed at the top of the panel. The circuit breakers with

indication lamps are provided for 230V, 48V and 24V DC power supplies.

A fan tray is provided below the power supply unit. The 6U rack containing the Processor

and I/O module is placed below the fan tray.

The 6U rack has a motherboard, which can accommodate

up to 12 I/O module in addition to processor module

(PCU).

The sub rack consists of following hardware modules:

1) Process control unit (PCU)

2) Digital input card(DI)

3) Analog input card(AI)

1. Process control unit (PCU)

The PCU module contains a powerful 32-bit processor

(CPU), memory, serial channel interfaces and I/O bus

interface. The processor T805 has a built in 64-bit

Floating Point Unit (FPU), 4k bytes of on- chip RAM,

32 bit timer and a micro coded scheduler. The

processor supports multiple CPUs to be connected

through links in case higher computing power is

required.

2. Digital input card

The digital input modules have isolated 16 channel digital inputs. All inputs are

protected against high voltage surges. Input noise suppression and filtering allows

reliable operation in hostile conditions.

Galvanic isolation of the field signals from the logic circuitry is obtained through the

OPTO couplers. A ground line running through the center of optocouplers on both

sides of the PCB physically separates the field bus from the logic circuits and the



17

front bus. This protects the rest of the system in case any hazards occur in high

field circuitry.

LED indication is provided on the front panel for each channel. It lights on a high

input to the respective channel.

The processor can access any of the 16 channels through the front I/O bus.

3. Analog input card (AI)

The 16 channel isolated analog input module is a complete fully isolated input system

containing 16 different channels on a 6U Euro board. It is ideal for industrial

applications requiring measurement of non-isolated transmitter signals in the presence

of high common mode voltages and ground loop noise.

Each input channel consists of a highly reliable flying capacitor multiplexer utilizing

mercury wetter/ dry read relays. These inputs channels feed a stable instrumentationamplifier and conversion is accomplished by a 12 bit A/D converter. The result is an

input signal having noise immunity upto 100CMV (Common mode voltage)

The bard accepts 16 channel of analog signals as input. Depending upon the particular

channel selected, it provides an equivalent 12 bit digital data as output.

The signals are connected to the front D 37 female connector of the board.

When the board and the particular channels are selected, all the relays are actuated.

The capacitor, which was connected to the selected relay, will now be connected to

the input of the multiplexer ADG508.

The change over contacts thus provides necessary isolation during analog to digital

conversion.

The output of INA is fed to the input of ADC, which operate at 0-10V range. The

ADC converts this 0-10V to its equivalent digital value and store it in a buffer inside

ADC.

The software package delivered with S900 RTU allows handling both digital and

analog input/outputs.

The entities and related functions controlled by the S900 RTU include:

1) I/O capacity

2)

Multiple master station communications

3) Local data logging

4) Archiving

5) Local alarm

6) Synchronization



18

Basic structure of RTU is as follows:

SIC panel contains Transducers.

Transducer is a device, which provides a transformed output in

response to a specified measured value given as input.

The basic functions of transducer are:

1. To measure/ to sense the change in parameters.

2. To convert the measured values from one form into

another form, that is useful for further processing.

SIC has following types of transducers:

1) Power transducers (active power transducer, reactive power transducer)

2)

Voltage tranducer 3) Frequency transducer

4) OLTC (on load tap changer)

Output of current and 4 mA to 20 mA

Potential transformers current or

-10 to +10V

Output of transducer goes to the RTU panel

Working

The RTU is the supervision and control system for the unmanned operation of the electric -

power equipment. The SCADA-RTU read the analog value and the status value of breaker

status, power amount, voltage, power factor ratio and etc and it transmits their data to the

main system. The SCADA-RTU consists of a MODEM, a common control unit, a peripheral

unit, a power supply, a terminal unit and etc. The common control unit receives the control

orders of the RCC and decodes the received orders. And it supervises and controls the input-

output of the peripheral unit and performs the function, which transmit the results to RCC and

SCC. The peripheral unit is a unit, which controls the input-output of the field. It has a CPU

in itself and communicates with the common control unit. And it supervises and measures the

state of electric power equipment of the field. The terminal unit is a terminal block that is

able to combine physically the field and the peripheral unit and there is a line protection

circuit.

RTU is a system that continuously monitors status data & analog data. This data s transmitted

to a mater station. It also receives and executes control commands from the master station to

open and close output relays and operate controls on any connected IEDs.

The RTU is essentially a computer which can store and process data in digital form. RTUmaintain its own local database of all the points, which are to be measured and controlled and

RTU

Panel

SIC

Panel

Transducer



19

continuously updates the information. The RTU sends data to the master in response to

queries sent by the master (poll response method). Typically only information that changes

since the last query is sent to the master.

Analog information are received from current and voltage transformers. The output of thecurrent and voltage transformers are then sent to transducers. The output of these transducers

(4mA - 20mA) is sent to the analog card of RTU. A/D converter converts these analog

signals to digital form for use in the microprocessor of RTU. On the other hand status signals

are taken from voltage free contacts of CB(52a) to status card to monitored status of CB.

After processing RTU transmit this digital data to master station through Power Line carrier

(PLC) & microwave communication. The RTU sends data to the master in response to

queries sent by the master (poll-response method). Typically only information that has

changed since the last query is sent to the master.

2. Communication front end (CFE)

CFE is the hardware of SCADA. This has ports of each data.

The communication equipment and software that links the computer to RTUs is referred

as communication front end. One RTU is located at the site and the other at the remote

station.

Function of CFE: It drives the serial communication lines connected to the RTUs. The

CFE hardware configures consists of Ethernet controller‟s card several serial

communication cards. The number of communication cards depends on the number of

RTUs connected to where each card can support up to 16 communication lines withRTUs.

As shown in the figure below; there are main, modem, and stand by in CFE.



20

Standby is just the copy of main. This is used when main does not works. Interconnection

buses are connected from the standby to the modem. These are used for carrying data.

The Communication Front End performs two main functions :

1) It translates the RTU communication protocol into a standard protocol.

2) It concentrates a number of communication lines into a single interface to the

communication front end. This greatly reduces the communication loading on the

real-time application servers, freeing computing power for other more important

users.

3. Multiplexer (MUX)

In electronics, a multiplexer (or MUX) is a device that selects one of several analog

or digital input signals and forwards the selected input into a single line. A

multiplexer of 2n inputs has n select lines, which are used to select which input line to

send to the output. Multiplexers are mainly used to increase the amount of data that

can be sent over the network within a certain amount of time and bandwidth. A

multiplexer is also called a data selector.

Schematic of a 2-to-1 Multiplexer. It can be equated to a controlled switch.

Multiplexing is the method of combining many signals to make a composite signal.

This signal is then send to destination through medium.

In Shakti Bhawn (SLDC); there is time division multiplexing (TDM) is used. In

TDM data sends in form of frames.

MUX has baseband branching. We use 8Mbps MUX. This 8Mbps signal can be

divided into four 2Mbps signals, i.e. 4*2 Mbps.

MUXs are of three types:

1. DM2 MUX (used for single direction)

2. DN2 MUX (used for cross connection. It can store 20Mbps signals)

3. DB2 MUX (used for three directions)

2Mbps signal goes to DM2. Shakti Bhawan has four such DM2.

http://en.wikipedia.org/wiki/Electronics

http://en.wikipedia.org/wiki/Analog_signal

http://en.wikipedia.org/wiki/Digital_signal

http://en.wikipedia.org/wiki/Computer_network

http://en.wikipedia.org/wiki/Bandwidth_%28signal_processing%29

http://en.wikipedia.org/wiki/Bandwidth_%28signal_processing%29

http://en.wikipedia.org/wiki/Computer_network

http://en.wikipedia.org/wiki/Digital_signal

http://en.wikipedia.org/wiki/Analog_signal

http://en.wikipedia.org/wiki/Electronics



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DM2 (Primary Multiplexing Equipment)

The DM2 is a member of the nokia Dynanet family of multiplex, branching, cross-connect

and line equipment. The DM2 performs the functions of dynamically controllable primary

multiplex equipment utilizing the Dynanet channel unit selection.

Basic Concept

The heart of the equipment is a MUX unit which is common to all channel and special units

of the DM2 system. The MUX unit communicates through a 2Mbit/s internal bus with the

tributary units and carries out the 2048Kbit/s framing according to ITU-T G.732 standard.

The common MUX unit also inserts the signaling information into time slot 16 or provides

the time slot 16 as a 64Kbit/s data interface, e.g. for use with a separate signaling equipmet.

Dynanet channel units

Analogue and digital services are realized with interface-specified channel units that connect

to the Dynacard bus. The channel units contain from one to ten voice/data channels,

depending on the complexity of the interface.

Each individual voice or data channel can use any 64Kbit/s time slot, several time slots or

only part of the capacity of one time slot. The allocation of time slots to different voice/voice

channels is independent of physical unit placement.

The dynamic branching equipment DB2 and the cross connection equipmen DN2 increase the

flexibility and application.

One-way Branching

The DM2 can be equipped with one of several 2Mbit/s Dynanet channel units to provide

efficient digital one-way branching in chain and tree etworks. Channels from different sites

can be freely and dynamically combined into a common 2Mbit/s frame. The dynamic

allocation provides a possibility of changing branching configurations during nomal

operation, allowing the flexible utilization of transmission capacity in rural and corporate

networks.

Main Characteristics

I TU-T recommendations G.703 and G.823

Bi t Rate 2048 Kit/s ± 50 ppm

Bi ts per time slot 8

Time slots per fr ame 32

Time slots for voice and data 30 (31 without CAS)

Frames per mu lti fr ame 16



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Multiplexing synchronous 32 Kbit/s time-slot interleaving

Peak vol tage/ impedance : 2.37 V± 10% / 75Ω

Pulse width : 244 ± 20ns

I nput signal attenuation : 0…6 dB / 1MHz

Technical Highlights

Any mix of voice and data interfaces using the wide selection of DYNACARD channel

units.

Easy adaption to future services

Decentralized powering for reliability

One- way digital branching

Dynamic local or remote control of equipment parameters Local or remote control of equipment parameters

Centralized network management

Several installation options

Software settings are used to set , for example, the following functions :

Time slot selections

Level settings

Impedance settings

Signaling and data interface parameters Loopbacks

Alarm functions



23

There are four DM2 used in Shakti Bhawan.

A 3/7 connector is used to connect the DM2 with computer. It connects to micro Sd card,

so we can access all the channels.

Functions of DM2

In the Receive Direction are:

Convert the input signal complying with ITU-T rec. G.703 to agree with equipment logic

sections, disassembling the line code, generate the R X direction clock signal.

Synchronous to the incoming signal frame.

Control the demultiplexing occurring in the channel units.

Monitor the error ratio of the received signal and recognize AIS

Recognize Alarm Indication Signal (AIS)

In the transmit direction are:

To generate TX Direction clock Frequency of 2048 Kbit/s

Control the TDM occurring in the channel units.

Form the output signal frame

Generate the interface signal complying with ITU-T recommendation G.703, as HDB3

line coded.

Applications

The DM2 equipment has been designed for multiplexing analogue speech and signaling aswell as data channels of different bit rates into a common 2 Mbit/s frame. It can be used:

As a traditional PCM multiplexer in subscribe and junction line networks.

In corporate networks to provide full range of voice and data services

As one-way branching equipment to enable efficient use of channels in rural areas or in

private networks.

For efficient data multiplexing, e.g., X.58, V.110 and Ethernet.

DB2 (Digital Branching in Networks of small capacity)

This is used for dropping the data. So this is also called Insert Drop Mutiplexer.

Digital branching equipment the DB2 is a member of the Nokia Dynanet Family of

access network products. The DB2 performs the functions of branching equipment that

can be controlled dynamically, using the Dynanet channel unit selection.



24

Digital branching principles

The DB2 branching equipment forms a 2 Mbit/s bi-directional branch to the main line signal.The branch and the main line signal have the same speed and frame structure. Individual

channels are connected through or branched and the operation is completely digital.

Dynamic branching

Dynamic branching makes it possible to change branching configurations during normal

operations. This unique feature makes it possible to fully and flexibly use the transmission

network capacity.

The various branching alternatives are stored in each DB2 in the network. The network

reconfiguration can be done manually through the service interface or it can be triggered

automatically, based on e.g. alarms or the time of day. Changes in banching do not disturb

traffic on those channels that remained unchanged.

The four main DB2 configurations are:

DB2B, basic branching equipment

DB2P, protected branching equipment

DB2T, terminal(change-over) equipment

DB2B-LP loop protected branching equipment

The DB2T selects the faultless signal in the receive direction and duplicates the signal in the

transit direction.

Channel units

Dynanet channel units can be connected to all DB2 configurations. The VF and data interface

units are connected directly to the internal 2Mbit/s bus of the equipment.

Each unit and channel can be programmed for any time-slot. The DB2, the DM2 multiplex

equipment and the DN2 cross-connect equipment all use the same Dynanet channel units.



25

Common channels

The DB2 supports both VF and digital commaon channels. The VF-type common channel is

based on the summing of PCM-coded signals, typically used for:

Polling data connections Base station systems for mobile phones

Service telephone ystems

Main characterstics

I TU-T Recommendations G.703, G.704, G.732, G.706, G.823, G.821

Bi t Rate 2048 Kit/s

Bi ts per time slot 8

Time slots per fr ame 32

Time slots for voice and data 30 (31 without CAS)

Frames per mu lti fr ame 16

Multiplexing synchronous 32 Kbit/s time-slot interchanging

Branching

Branched time-slots : 0-30(31) time slots

VF (PCM) omnibus channels : 0-30(31) time slots

Digital omnibus channels : 0-30(31) time slots

Bi t rate of each branched channel: 32….1920 Kbit/s (nx32 Kbit/s)

Control of branching: via the service interface

Electrical interfaces 2Mbit/s

ITU-T Recommendations G.703, G.823

Bi t Rate 2048 Kit/s ± 50 ppm

Code HDB3

Pul se shape rectangular

Peak voltage/ impedance 3V/120 ohm, 2.37V/ 75 ohm

Peak vol tage tolerance 10%

I nput signal attenuation 0 to 6 db/ 1MHz



26

VF and data interface units of the dynanet family are detailed in separate leaflets

Number of VF and data uni ts limited by sub rack space only

Applications

The DB2 equipment family offers a wide range of different branching and drop/insert

functions. Typically, the DB2 is used in private cahin, tree or ring-shaped networks. In applications where dynamic network structure is the optimum solution, the DB2 is he

key component

In public networks, dynamic branching can be used to establish semi-permanent or leased

speech and data lines. The DB2 is also well suited for data network applications.

Functions of DB2B B2 unit:

Provide 2 x 2 Mbit/s interfaces (Direction #1 & #2)

Perform the settings and control coming via service interface and command bus.

Controls equipment in fault condition.

Generate Master clock, synchronized t incoming signal (R x 1..3) or external.

Handles alarm indications using LED‟s & Rack alarm lam ps.

Any direction (1,2 or 3) can be set for „In use‟ or „Not in use‟ mode

Code data hybrid.

Monitor the error ratio of the received signal and recognize AIS.



27

Functions of DB2B X2 unit:

Provide 1x2 Mbit/s interface or access to time slots via channel units.

Realizes timeslot connections to TX direction in compliance with branching tables.

Synchronization interfaces for external clock and provide equipment clock for other

equipment

Monitor the error ratio of the received signal and recognize AIS.

DN2

Decentralization of connection information

The cross connection is stored in the interface units (IU2)

Duplication of 2M connections (1+1 redundancy)

A 2 Mbit/s signal is brought to/sent from two different ports in the DN2 via two different

transmission routes, the DN2 selects the better of these.

Duplication of equipment

The bus and the cross-connection can be duplicated it the node size is less than or equal

20 ports. Also the Bus Power nit can be duplicated.



28

Conditional connection tables

The DN2 can be defined to change connection tables on the basis of a condition. This

way it is possible to implement e.g. N+1 redundancy.

Channel specific redundancy in a loop network n* 8 Kbit/s channel protection using a pilot bit.

DN2 Block Diagram

DN2 is a digital cross-connect with add/drop and multiplexing capability. DN2 has its own

2Mbit/s internal bus giving connection capacity for 30 channels enabling in to function as a

cross-connection switch with an internal primary multiplexer. If the terminating circuit

capacity at a DN2 site is greater than 30, additional DM2 multiplexer can be connected to the

available 2M interface ports. Each DN2 has its own 19‟‟ subrack. DN2 can be controlled

locally or remotely by the Service Terminal, or the Network Management System. DN2 in

this project will be configured for 16 x 2 Mbit/s interfaces.

The DN2 consists of the following units : a control unit (CU), 1 TO 2 bus power units (BPU)

0 to 17 channel units and 1 to 20 interface units (IU2)

Technical Specifications

The frame and multiframe structures comply with ITU-T recommendations G 703/706

Equipment meets the 2 Mbit/s jitter and wander requirements defined in ITU-Trecommendation G.823



29

Digital Interfaces

2048 Kbit/s Equipment Interfaces

The interface complies with ITU-T recommendation G.703

Transmitter characteristics

Peak Voltage 2.3 V / 75 Ω

No- pulse level 0.275 V/ 75 Ω

Pulse width 244 ns ± 20 ns

Receiver characteristics

Attenuation at 1 MHz <6 dB

Impedance 75 Ω

Return loss > 18 dB / 0.1….2.1 MHz

Synchronization Interface 2048 kHz

The interface complies with ITU-T recommendation G.703.

Synchronization output

Frequeny 2048 kHz ± 50 ppm

Impedance 75Ω

Amplitude 1.5….3.0 Vpp / 75 Ω

Synchronization input

Frequeny 2048 kHz ± 50 ppm

Impedance 75Ω

Amplitude 1.5….3.0 Vpp / 75 Ω

Allowed attenuation 0…6 dB

Return loss >15 dB / 2048 kHz

Measurement inetface 2048 kbit/s

The outgoing or the incoming 2048 kbit/s

signal of each 2 Mbit/s interface can be

measured through this interface. At the CU ,

measurements can be performed for the TX or



30

the R X clock, as well

Bit rate 2048 kHz ± 50 ppm

Peak Voltage 2.3 V / 75 Ω

No- pulse level 0.237 V/ 75 Ω

Pulse width 244 ns ± 20 ns

Digital Microwave Radio (DMR)

Microwave radio is a data transmission method commonly used in the telecommunications

industry. Using a microwave radio relay, these service providers can transmit digital and

analog signals across long distances. Microwave radio is known as a “line of sight”technology. This is because microwave data is transmitted between two microwave radio

towers in different locations. Once a clear path has been established, transmissions between

directional antennas on two microwave radio towers can occur.

Digital microwave RF is a more technologically advanced microwave data transmission

method. The higher bandwidth of digital microwave RF provides for increased data

transmission by supporting more verbose protocols. Digital microwave RF is faster,

decreasing system poll time as well.

NOKIA DMR 2000

PROPERTIES OF NOKIA DMR 2000

The radio relay equipment DMR 2000 operates in the 1.7…..2.7 GHz frequency band,

and the maximum output power is 30 dBm

The DMR 2000 can transmit two, four, eight or sixteen 2 Mbit/s G.703 signals or one 34

Mbit/s signal. An 8 Mbit/s interface can be implemented by using an external (DM8 –

second order multiplexer.

The frequency allocation meets the recommendations by ITU-R. The use of the radio

frequency spectrum has been optimized at all transmission capacities.

In this project the radio relay equipment is used to transfer 4 signals at 2 Mbit/s each

(G703). By means of the integrated n x2 Mbit/s multiplexer, DMR enables the direct

access to 4 x 2 Mbit/s signals. Also drop/insert and cross-connection facility between any

2 Mbit/s bit streams can be executed.

There are two transmitter power options : 20 dBm and 30 dBm. These correspond to an

output of 0.1W and 1W respectively.

In addition, the output power may be adjusted either by manually or automatically by

means of ALCQ feature (Adaptive Level Control with Quality Measure) withi wide range

(15 dB) to optimize the route.



31

The digital radio relay equipment family is fully compatible with the Nokia

telecommunications Transmission Management System (TMS), and it also complies with

the telecommunication Management Network(TMN) architecture standardized by ITU-T.

All the commissioning and transmission management functions of the DMR 2000

(Software settings, control, measurements, and fault location) may be performed by either locally with handheld service terminal of remotely by TMS.

Mechanical construction

The RF boards of the transmitter and receiver and the modem board of the radio relay

equipment are mounted in an aluminium chassis. The motherboard is mounted to the cover

on the modem side.

The power supply unit which generates and regulates the operating voltages required has

been mounted to the motherboard. The motherboard is connected to the Baseband Unit

(BBU) ad in the 16 x 2 Mbit/s variant also to the Expansion unit (EXU). This entity has been

installed in a cartridge made of steel sheet metal.

The front connectors have been covered with a front case to provide interference shielding.

The antenna and loop mixer are attached to the cartridge. A Euro connector for the Service

Terminal is located in the front of the loop mixer. This connector may also be used to

recharge the Service Terminal batteries. The RF branching, baseband branching and

circulator needed in redundant operation are fastened outside the cartridge.



32

The dimensions of the cartridge are (including filter) 445 mm (height), 120 mm (width) and

305 mm (depth from front edge of cooling extension to rear edge of rack).

At equipment station , the cartridge is suspended by the brackets at its rear wall to the

equipment rack. It may be installed in a Nokia TM4 rack (CEPT-A slim rack)

Structure of antenna filter and loop mixer

In redundant set-ups, the two equipments are installed vertically, the lower bit equipment

upside down. The radio relay equipment may also be installed in a 19‟‟ rack, an M80 rack, anoutdoor cabinet or it may be mounted on the wall using the installation accessories. In

redundant set-ups, the two equipments are then installed side by side. In single use, the

equipment may also be installed horizontally.

The main channel interfaces (2Mbit/s) may be either balanced using Euro connectors or

unbalanced using coaxial connectors (SMB) at the 34 Mbit/s capacities, the main channel

interface is always implemented by means of coaxial connectors. The front connectors and

the power switch of the radio equipment are located behind the front case. The measurement

point connector MP is accessible without having to open the front case which provides

protection against interference. Only the cables for the repeater bus and protection bus , if anyare connected to the rear of the cartridge.

Functions of baseband unit:

The BBU multiplexes the 2 Mbit/s main channels so that each channel may be placed into

any time slot of the radio frame (by means of the Service Terminal Settings). At the repeater

station the Service Terminal may also be used to specify without restrictions which channels

shall be directed to the interfaces at the station for branching and which channels will

continue on the repeater bus to the next radio hop. In addition to the 2 Mbit/s main channels,

the following information is multiplexed into the frame structure.



33

Block Diagram & Interfaces

Figure shows the block diagram of DMR 2000 radio equipment. The equipment may be

divided on the block level into the baseband and radio sections, the mother board and the

power supply.

The baseband section includes the baseband unit (BBU) with 2 x 2 Mbit/s, 4 x 2 Mbit/s, 8

x 2 Mbit/s or 1 x 34 Mbit/s interfaces.

The radio section consists of modem and the RF parts which are further divided in to

transmitter, receiver and antenna branching.

The power supply is connected to the motherboard which distributes the operating

voltages to the other parts of equipment.

Main Channels

The N X 2 Mbit/s and 1 x 34 Mbit/s main channel interfaces of the DMR 2000 meet the

ITU-T recommendations G.703

In addition to main channel interfaces, the radio equipment provides auxiliary channel

interface and external inputs and outputs.



34

Auxiliary Channels:

Auxiliary channels consists of one service telephone channel with two interfaces, Data

channel DI1-DI4 in which DI1 is operating at 9600bit/s and can also be used for

TMS.DI2-DI4 three asynchronous channels operating at 1200…4800 bit/s depending on

total capacity of the system.

External inputs and outputs

Five digital (PI1I, PI2I, PI3I, PI4I, PI5I) and one analog input (PI6I) for external alarms

& five digital control outputs (PA1.PA2.PI30, PI40, PI50)

Front view of DMR 2000

DMR 2000 has two parts- one has radio and second has Masters & Slaves for east and

west sub-LDCs. Diagram of DMR is shown below:



35

As seen in diagram, there is used master and slave technique. In this technique master can

use both of it‟s TX and R X, but slave cannot use it‟s R X. To use the R X of slave , first

convert slave into master and then use both TX and R X.

There is a green light which glows on use of master.

As we study earlier that there is four 2 Mbps signals exists in Shakti Bhawan, thesesignals have ports in DMR. There are four connections in which each is of 2Mbps.

LEDs are also connected which glow when radio access.

Filter is used for frequency change purpose. Filters are connected with MDF (Main

Distribution Filter).

Motherboard is connected to BBU.

Output power is control by ACQL (Automatic Quality Control Level).

Methods of redundancy

i. Hot standby operation (HSB) ii. Warm standby operation (WSB)

iii. Hot standby operation with space diversity

iv. Frequency diversity

v. Polarization diversity

vi. Pace diversity with 2 TX

Technical Specifications

Frequency range 2.3 – 2.5 GHz

Interface connector SMB coaxial 75Ω

TX output power 1 W

Duplex frequency 95MHz

Capacity 4 x 2 Mbit/s

SCADA (Supervisory Control And Data Acquisition)

SCADA stands for Supervisory Control and Data Acquisition – any application that gets

about a system in order to control that system is a SCADA application.

A SCADA application has two elements:

1) The process/ system/ machinery you want to monitor a control – this can be a power

plant, a water system, a network, a system of traffic lights, or anything else.

2) A network of intelligent devices that interfaces with the first system through sensors

and control outputs. This network, which is the SCADA system, gives you the ability

to measure and control specific elements of the first system.



36

Where is SCADA used?

SCADA can be used to manage any kind of equipment. Typically they are used to automate

complex industrial processes where human control is impractical – systems where there are

more control factors, and more fast-moving control factors, than human beings can

comfortably manage.

Around the world, SCADA systems control:

1) Electric power generation, transmission and distribution.

2) Water and sewage

3) Buildings, facilities and environments

4) Manufacturing

5) Mass transit

6) Traffic signals

Common System Components

A SCADA system consiste of the following sub-systems:

A human – machine interface or HMI is the apparatus or device which presents process data

to a human operator, and through this, the human operator monitors and controls the

process.

A supervisory (computer) system, gathering (acquiring) data on the process and sending

commands (control) to the process.

Remote terminal units (RTUs) connecting to sensors in the process, converting sensor

signals to digital data and sending digital data to the supervisory system.

Programmable logic controller (PLCs) used as field devices because they are more

economical, versatile, flexible, and configurable than special-purpose RTUs.

Communication infrastructure connecting the supervisory system to the remote terminal

units.

Transducer

TRANSDUCER

Transducer is a device, which provides a transformed output in response to a specific

measured value given as input.

The basic functions of transducer are:

1) To measure/ to sense the change in parameters.

2) To convert the measured values from one form into another, that is useful for further

processing.

The transducers Panel at SLDC has 11 Transducers, out of which 8 are the main Transducers

and 2 are voltage Transducers, and one is Frequency transducer. The main transducer consists

http://en.wikipedia.org/wiki/User_interface



http://en.wikipedia.org/wiki/Remote_Terminal_Unit

http://en.wikipedia.org/wiki/Data_acquisition






http://en.wikipedia.org/wiki/Remote_Terminal_Unit




37

of 4 CTs (only R&B phases), 3PTs, 1 neutral point, 1 earth point, 2 points for dc supply (48

V, to energize the T/D), 2 points of Ms and 2 points for MVARs.

Potential Transformers (PTs) and Current Transformers (CTs)

Transformers used for the measurement of voltage are called potential transformers. The primary winding is connected to the voltage being measured and the secondary winding,

to a voltmeter. The PT steps down the voltage to the level of voltmeter specification used

in the project. Here this is 110 KV/ 110 V

Transformers used for the measurement of current are called Current Transformers. The

primary winding of a current transformer is so connected that current being measured

passes through it and the secondary winding is connected to an ammeter. The CT steps

down the current to a lower level. The current transformer is used with its primary

winding in series with the line carrying the current to be measured.

Modem

The term MODEM is an acronym for Modulator- Demodulator.

The primary modem function is to convert digital data into analog form, which is suitable

for transmission on common carrier circuits. Modulation is the D/A conversion in which

the digital data is placed on the transmission line by modulation of a tone or carrier.

Demodulation is the reverse process.

Three modulation techniques are commonly used:

i. Amplitude modulation

ii. Frequency modulation

iii. Phase modulation

Modems operate with one functioning as an originate unit and the other as an answer

unit.

The originate modem transmits on a low frequency channel, using 1.27 KHz for a mark

and a 1.07 KHz for a space. It receives on a high frequency channel using 2.225 and

2.025 KHz respectively for a mark and space.

The answer modem transmits on the high frequency channel and receives on the lower frequency channel.

The timing circuit provides the basic clocking information for both the transmission as

well as reception of signals.

A crystal oscillator to within about 0.05% of the normal value usually controls the

internal timing.

Modem is used to adjust the output level of data the computer data is converted to analog

waveforms as carrier and this composite signal passes through our common telephone

lines to reach the destination, where the carriers is removed and the original data is given

to the computer.



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This is connected between computer and the telephone lines, in the information

technology industry, computer is known as Data Terminal Equipment (DTE) and modem

is known as data communication Equipment (DCE). Modems are classified by their data

rates.

Functional Overview

The purpose of the SCADA subsystem is twofold:

a) It maintains an up-to-date picture of the state of the monitored system in its database. This

allows operators to observe the state of the monitored process by simply examining the

database via CRT displays. This SCADA database also provides the other programs in the

system access to the real-time SCADA data.

b) It allows operators (and other programs) to interact with the monitored process by

transmitting controls to the process.

c)

The Historical Data Recording (HDR) function records all changes to selected data in

journal files both during normal and disturbance conditions. Each file contains an initial

snapshot and then a journal of data changes.

d) The sequence of events unction provides information (status changes, instantaneous

measured values) with highly accurate time for devices monitored by suitable RTUs.

e) The Generalized Calculation (GENCALC) function provides a means for the operator to

derive calculations in a real-time environment.

f) The tagging function permits the placement and removal of tags from devices in the

system.

g)

The loadshed function (load shedding and restoration) is used in emergency situations toautomatically shed load from the power system.



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Data Acquisition

Data is retrieved from the monitored network by an integrated combination of hardware

and software in the real-time application server (“ host SCADA”), Telemetry Front End,

communication front end and RTUs.

The system maintains communications statistics database that keeps a record of all

communication failures for assisting maintenance personnel in detecting deteriorating

communications facilities.

Data Flow

The most important role of the RTU is to interface with the monitored system. This is

done through three types of input data : digital inputs, analog inputs, and pulse

accumulator inputs.

This data is collected and stored for transmission to the communication Front End (CFE).

Message numbers, error detection codes, acknowledge and negative-acknowledge codes

and exchanged along with the data to securely transfer the information To the

Communication Front End.

The communication Front End translates the data from the formats returned by RTUs to

the RTU protocol independent format used in the communication Front End.

By the host SCADA this data is entered into the RTU hierarchy as a „raw‟ value.

Engineering unit‟s conversion is then done, followed by limit checking. At each step of

the processing, quality codes are set, and alarms may be issued.

Once the data is in the host, processing into the SCADA database begins.

Data Processing

the major function of the data processing module is to place the data retrieved from the RTUs

in the database. All data is placed into the database un a standard form: digital status in a

standard two-bit configuration, analog and accumulator data as single-precision floating point

in engineering units.

Three types of information are maintained in the database:

a) Status values, such as circuit breaker position (tripped/closed)

b)

Analog values, which are process variables measured by the RTUs (temperature, pressure

etc.)

c) Pulse accumulations, which usually represent quantities delivered (such as MWh of

electricity).

Supervisory control

Supervisory control is the SCADA function used to issue control commands to field

equipment (digital devices, set points) under the supervision of the RTUs, from the

operator or from another application through a user-callable Apllication Programming

Interface (API).



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Nokia Network Management System /100

Purpose of NMS

Supporting the network operator in planning the network evolution and reconstructing of

the network (e.g., by adding additional network elements)

Supporting efficient maintenance activity.

NMS offers the function of fault management, Configuration management.

Logging in

Before you can operate Nokia NMS, you need to get a user name and password from your

system administrator. The system uses them to identify you. Without them, you cannot use

the Nokia NMS.

Logging out

The earliest way to log out is to click the Exit button on the VUE Workspace Manager.

Monitoring

By using following function we can monitor all the sub-stations and sub-LDCs

There are various alarms which gives fault status anywhere in the whole system.



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Alarms

There are tree Fault Management Monitoring Applications:

I. Alarm viewer

II. Alarm monitor

III.

Alarm history

Alarms are of two types- major and minor. They are recognized by their colours. Mojor

alarms are represented by red and minor alarms by yellow or other colours.major alam comes

when a fault effect the system.

Example:

1) E-3 (Major Alarm) – This alarm comes when we send 10 microwave signals but receive

only three at destination.

2) E-5 (Minor Alarm)

3)

AIS 2M – When system fails then this alarm comes.

4) Fall in equipment – Let a and b be two radios. When „a‟ is not working then „b‟ receives

this alarm.

5) Loss of supervision – When one place cannot monitor the other place then this alarm

comes.



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Exchange

Telephone exchange

In the field of telecommunications, a telephone exchange or telephone switch is a system of

electronic components that connects telephone calls. A central office is the physical building

used to house inside plant equipment including telephone switches, which make telephone

calls “work” in the sense of making connections and relaying the speech information.

The exchange code or central office code refers to the first three digits of the local number

(NXX).

3 Types of exchange:

a) Local

b)

Tandemc) International

Local Exchange – connect to the customer (subscriber).

Tandem Exchange – A telephone central office switch that links Telco end offices

together and does not connect to the customer directly.

International exchange – connects exchange to entire country and oversea.

Switched calls are dialable (users dial a telephone number to make a connection).

People can reach anyone on public network by dialing a telephone number.

A network consisting of at least one switching system (exchange) and accommodatedtransmission lines (optical fiber microwave) is referred to as a telephone network.

Function of Exchange

Records customer‟s call meter.

Monitor switching process between exchange and

customer

Record customer‟s request (meter termination).

Provide supervision tone such as dial and busy tone.

Control conversation quality and exchange service.

Switching Network

a) Concentrator

b) Distributor

c) Expander

d) Multiplexer



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Block Diagram Of Telephone Exchange

Exchange has several cards for communication between users.

There are six cards as:

1) Communication Group Card – used so that many users can communicate with each

other without interfering each other. Any two users can communicate with each other.

2) Ear and Mouth Card – used so that users can speak and hear the information these are

Trunk cards that are used 8 ports. STD calls are called trunk calls.

3) Conference card (CNF) – Multiple users can talk to each other at the same time.

4) Port file control card (PFC)- used for scan all the ports on the exchange. There are 256

ports.

5) Announcement and Tone Detector Card (ATD) – It gives the busy or the dialing tone



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Besides above cards there are computer, processor, power supply and internal buses.

Computer is used for control the whole system.

Processor is connected to the computer. It is P01 processor which has EPROM or

EEPROM.

Exchange has 48V DC power supply and it has 250 mA current. Power supply system

generates +5V or +12V power.

Internal buses can access 2Mbps data at a time.

Every card has 8 ports in which two ports are TX, two ports for RX, two ports for TX

signaling and remaining two ports for RX signaling.

There is a stand by (i.e. copy) of above card system. If any card fails then copy of that card is

used.

Block diagram of exchange:

Exchange is divided into three parts. These are called as COPY0, COPY1 and POWER

SUPPLY. Every copy has one PFC and ports such as P0, P1,P2 and so on. Power supply is

48V DC which is used to generate +5V r +12V power.

Telephone Number

A telephone number is a sequence of digits used to call from one telephone line to another ina public switched telephone network. When telephone numbers were invented, they were

short- as few as one, two or three digits – and were given orally to a switchboard operator. As

phone systems have grown and interconnected to encompass the world, telephone numbers

have become longer. In addition, they access other devices, such as computers and fax

machines.

There are 9 numbers in a phone number. In these 9 numbers first is STD code of country,

then two digits are for Area code (area such as Delhi, U.P. etc.) , then tree digits for

Exchange ID and last three digits are directory numbers.



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Suppose there is a number abcdefghi. This number can be explained as:

The number contains the information necessary to identify uniquely the intended endpoint for

the telephone call. Each such endpoint must have a unique number within the public switched

telephone network. Most countries use fixed length numbers and therefore the number of

endpoints determines the necessary length of the telephone number.

POWER SUPPLY SYSTEM:

The system CS 48/1900 is a convection cooled power supply system (CS= Convection

Cooled System), which provides a non-interruptible power supply for telecommunications

equipment. The system consists of rectifier modules, the battery connection, DC- Distribution

and controller of the type PSC-1000

The system performs the following tasks:

Protect sensitive consumer groups against interruption of the power supply. In the event

of the mains power failure, the batteries take over the task of supplying the power to the

consumer interruption.

Supplies the consumer with the stabilized voltage. Voltage variations caused by witching

processes are regulated out.

Supplies the batteries with a tightly controlled charge maintenance voltage.

Isolates the mains and consumer circuits from one another at all stages of the power,

control and regulation circuits.

Prevents interference pulse breakthrough or transmission from or to the mains by means

of appropriate filters.

Provides reliable monitoring and rapid alarm triggering in the event of a fault.

Functional description

The rectifier modules operate according to the principle of direct supply parallel to the

batteries and to the load. The deliver the full load current and they provide the batteries with

the optimum charge maintenance voltage.



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By means of inter-modular load current distribution the total current is delivered in equal

parts by each rectifier module. The circuits for system monitoring detect abnormal voltages,

short circuitry, mains failure and overheating by means of a comparison with preset values.

Alarm signals are generated according to type and/ or importance of this failure. LEDs

performs the display at the rectifier modules and on the controller display.

1) AC- source Mains, 230V AC, 3 – phase

2) Rectifier module protection Magnetic circuit Breakers(MCB)

3) Rectifier modules SMPS 48V – 1900 W

4) Relay Low voltage disconnection LVD of the battery

5) Battery Battery or battery group

6) DC – output 48 V

7) Controller Overall system controller PSC 1000 evaluation

Power stack battery

The power stack batteries are maintenance free type and work on oxygen recombination

principle. The oxygen gas generated at the positive plate, is transported in the gas phase

through a highly absorbant and porous glass separator to the negative plate. The micro porous

glass separator is not completely saturated with electrolyte and the void space thus available

allows an unimpeded access of oxygen to the negative plate. The oxygen gas gets reduced at

the negative plate surface, thereby effectively suppressing the evolution of hydrogen.

Consequently, power stack cell do not lose any water under normal operation and therefore

no toping up is required.

Voltage: Power Stack cells are 2V units, which are assembled, in modular racks to get 2V,

6V and 12V modules. These racks are mounted horizontally and can be stacked one above

the other. For maximum service life, the recommended float voltage is 2.23 volts per cell.

Power stack cells are normally rated to an end cell voltage of 1.76 volts per cell where it is

necessary to terminate discharge at higher end cell voltage due to reason of equipment

compatibility , it can be done providing higher rated capacities.

Chargers: Power stack cells should be charged with constant potential charges. The charging

current should be limited maximum of 0.2 C10. The widely accepted charging methods use acurrent of 0.1 C10. Float charging is at 2.23 VPC. If the charger does not have a float-cum-

boost mode, it is important to switch over to float either after boost not later than 24 hours

under steady current conditions.

Applications: Power stack cells are designed especially for stand by applications. The deep

discharge cycle performance combined with excellent float characteristics make Power Stack

the ideal choice for a wide range of industrial applications like telecom, power generating

stations and substations, uninterrupted power supplies , railways and solar photo voltaic.



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BILLING

When you buy electricity they charge you by the kilowatt-hour (kWh). When you use 1000

watts for 1 hour, that's a kilowatt-hour.

To get kilowatt-hours, take the wattage of the device, multiply by the number of hours

you use it, and divide by 1000. (Dividing by 1000 changes it from watt-hours to kilowatt-

hours.)

Here's the formula to figure the cost of running a device:

wattage x hours used ÷ 1000 x price per kWh = cost of electricity



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Conclusion

Modern economies are dependent on reliable and secure electricity services. Electricitymakes an essential contribution to economic performance, international competitiveness and

community prosperity. The society‟s dependence on electricity shall intensify as the world

moves ahead in the twenty- first century.

A knowledge of electricity and its principles and the means through which they are directed

to the service of mankind should be a part of the mental equipment of everyone who pretends

to education in its truest sense.

The project is based on the dedicated machinery, technology, equipments and manpower

working to ensure smooth functioning of the grid. The project will benefit those who haveinterest in the instrument and will provide the reader with the deeper knowledge of the topic.

It is matter of great prestige to be a part of well & highly organized UPPCL. After being a

part of such organization one has the chance to learn a lot about a successful organization.

Besides this it also imparts the opportunities to strengthen the particular‟s professional skills.

This department helps in all possible ways to guide the functions, working process, units

prepared of the organization. One can learn a lot if he takes the proper interest.



REFERENCE

1. www.uppcl.org

2. www.google.co.in

3. www.wikkipedia.com

4. Manuals of units

5. Manuals of SLDC

http://www.uppcl.org/


http://www.wikkipedia.com/




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