REPORT ON INDUSTRIAL VISIT

By: Nikhil Vadera, B.Tech. III Sem (ECE)Guided by: Submitted to: Prof. O.P. Vyas, HoD, ECE, JIET, Jodhpur

Purpose To gather knowledge and information about different devices, equipments and technologies in the area of Electronics and Communication Engineering.

Place of visit 400KV GSS, Surpura (Mandore)

Date: 12 October 2009 Time: 10.45 A.M. – 01.00 P.M.

GSS InstructorsRajendra Bohra (PLCC)S.S. Tanwar (Control Panel)Mr. Basant (Engineer from ABB company explained about SCADA software and RTU)

The basic function of Grid Sub-station (GSS) is to receive power from various sources and distribute/supply to various locations of the city. The Surpura located close to Mandore is highly modern GSS equipped with the following facilities:

PLCC Model 9505

The Model 9505 V3 Power Line Carrier System from BPL Telecom is a fully integrated, voice/ data switching system capable of supporting the most demanding networking communication environments between electricity board substations.

This latest IC version system provides single or multiplexed voice grade channels for transmitting speech or audio tones over high-voltage transmission lines (400KV/220KV/132KV) and insulated static lines. The transmitted audio tones can be used for:

1. tele-metering,

2. Supervisory control,

3. Protective relaying, data and for other purposes.

This is a single-side-band (SSB) carrier system that uses the available frequency spectrum more efficiently than all other modulation techniques. Each terminal is available as either a single or twin

channel unit. Each channel provides a voice-grade circuit over the transmission medium.

The equipment can be configured for "speech-plus" operation (simultaneous transmission of speech and audio tones). When used for data only, each channel can carry up to twenty-four 50-baud telegraphic/ data channels.

The operating carrier frequency band of 40 - 500 kHz is available in a single filter, which is an added advantage to the power utility.

The product has amplifier ratings of 40 Watt and 80 Watts.

FEATURES

One MODEM

One speech interface module

One data interface module

A power supply unit

An amplifier

A line filter

An optional synchronizer module

A two 19 inch double Euro chassis. The typical terminal also contains a RF line interface assembly

It is connected to the Battery, which works on 48V.Battery work in two modes – Boost and Float.

CONTROL PANEL

Company-Siemens

The control panel controls the distribution of power supply from the main transformer of 400 kV to various transformers of 220 kV for the city supply.

SCADA

SCADA stands for supervisory control and data acquisition. It generally refers to an industrial control system: a computer system monitoring and controlling a process.

A SCADA System usually consists of the following subsystems:

• A Human-Machine Interface or HMI is the apparatus 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

RTU

An RTU, or Remote Terminal Unit is a microprocessor controlled electronic device which interfaces objects in the physical world to a distributed control system or SCADA system by transmitting telemetry data to the system and/or altering the state of connected objects based on control messages received from the system.An RTU monitors the field digital and analog parameters and transmits all the data to the Central Monitoring Station. An RTU can be interfaced with the Central Station with different communication media. RTU contain different cards-

Digital Input card (DI) Analog input card (AI) Digital Output card (OI) Analog Output card (AI)

And there is a basic rack which stores all data. An RTU can monitor analog inputs of different types including 4 to 20 milliamperes (4-20 mA)