Electrical Safety - Indian Standards

Electrical Safety – Indian Standards

In the field of electrical engineering, engineers and other professionals get exposed to electricity indirectly during generation, transportation, installation and usage. Such conditions might cause hazards if accurate safety measures are not taken.

To promote the safety and the right usage of equipment, there are certain rules and regulations formulated by the Bureau of Indian Standards (BIS). BIS follows the following five principles −

  • Safety
  • Ease of use and adaptability
  • Simple technology
  • Value for money products
  • Energy efficiency and environment

BIS has published the following code of practice for public safety standards in order to promote the right to information, transparency and accountability in a proper manner to the public.

Code of Practice for Electrical Wiring Installation

  • IS − 732 (1989)
  • Section − Electrical Installation
  • Application − Design of installation, selection and erection of equipment, inspection and testing of wiring system

Code of practice for Earthing

  • IS − 3043 (1987)
  • Section − Electrical Installation
  • Application − Design, installation and calculation of Earthing system

Lightning arrester for Alternating Current System

  • IS − 3070 (1993)
  • Section − Electro technical: Surge Arresters
  • Application − Identification, ratings, classification and testing procedure of Arrester

Let us now consider other important codes of practice established by BIS for the purpose of electrification. The codes are listed in the table below −

General Requirements
Sr. No. Standards & Application
1 IS:900

Installation and maintenance of Induction motors

2 IS:1271

Classification of insulating materials for electrical machinery

3 IS:1646

Fire safety of buildings (general) electrical installation

4 IS:1882

Outdoor installation of Public Address System (PAS)

5 IS:1886

Installation and maintenance of Transformers

6 IS:1913

General and safety requirements of electric lighting fittings

7 IS:2032

Graphical symbols related to electrical technology

8 IS:2274

Electrical wiring installations where system voltage is more than 658 volts

9 IS:3034

Fire safety of industrial buildings (Electrical generation and distribution stations)

10 IS:3072 (part-1)

Installation and maintenance of switchgear where system voltage is less than 1000 volts

11 IS:3106

Selection, installation and maintenance of fuse where system voltage is less than 650 volts

12 IS:3638

Guide for gas operated relays

13 IS:3646

Practice for interior illumination

14 IS:3716

Guide for insulation coordination

15 IS:3842

Guide for electrical relays for AC system

16 IS:4004

Guide for lightening arrestors (non-linear ) for AC system

17 IS:4146

Guide for voltage transformers

18 IS:4201

Guide for current transformers

19 IS:5571

Selection of electrical equipment in hazardous area

20 IS:5572

Types of hazardous areas for electrical installations

21 IS:5780

Intrinsically safe electrical apparatus and circuit

22 IS:5908

Measurement of electrical installations in buildings

Switchgear

The following table lists down the codes of practice for the maintenance of switchgear −

General Requirements
Sr. No. Standards & Application
1 IS:375

Making and arrangement for switchgear bus-bars, main connections and auxiliary winding

2 IS:694(part-1)

PVC insulating cables with copper conductors (where voltage is up to 100v)

3 IS:1248

Direct acting electrical indicating instruments

4 IS:2147

Degrees of protections for enclosures for switchgear and control gear (low voltage)

5 IS:2208

Guide for HRC fuse (up to 650v)

6 IS:3202

Guide for climate proofing of electrical equipment

7 IS:3231

Guide for electrical relays of power system protection

8 IS:4047

Guide for heavy duty air break switches and fuses for voltage less than 1000v

9 IS:4237

Requirements for switchgears and control gears for voltage up to 1000v

10 IS:5987

Selection of switches where voltage is up to 1000v

11 IS:335

Insulating oil for transformers and switch gear

12 IS:2516(part-1,sec-2)

AC circuit breakers (Tests for the voltage range 1000v to 11000v)

13 IS:3427

Metal enclosed switch gear and control gear for voltage within 1000v to 11000v

14 IS:722

AC electricity meters for 415 volts

15 IS:1951

PVC sleeving for electrical works

16 IS:2516(part-1sec-1 & part-2sec2)

AC circuit breaker (Tests for voltage within 1000v)

17 IS:2419

Guide for dimension of electrical indicating instruments

Motor Control Centre (MCC)

The following table lists down the codes of practice for the maintenance of Motor Control Centre −

General Requirements
Sr. No. Standards & Application
1 IS:1554(part-1)

PVC insulated heavy duty electric cables for the voltage up to 1100v

2 IS:1822

AC motor starters of voltage less than 1000v

3 IS:2959

AC contactors of voltage less than 1000v

4 IS:3961(part-2)

Recommended current ratings for PVC insulated and PVC sheathed cables

5 IS:5124

Installation and maintenance of AC induction motor starters within 1000v

6 IS:2959

Guide for AC contactors of voltage less than 1000v

Invertors

The following table lists down the codes of practice for the maintenance of invertors −

General Requirements
Sr. No. Standards & Application
1 IS:391

Mains transformers for electronic equipment

Transformers

The following table lists down the codes of practice for the maintenance of transformers −

General Requirements
Sr. No. Standards & Application
1 IS:335

Insulating oil for transformer and switch gear

2 IS:2026

Power transformers

3 IS:2099

High voltage porcelain bushings

4 IS:3637

Gas operated relays

5 IS:3639

Fitting and accessories for power transformers

Motors

The following table lists down the codes of practice for the maintenance of motors −

General Requirements
Sr. No. Standards & Application
1 IS:325

3-ph induction motors

2 IS:4691

Degrees of protection provided by enclosures for rotating machinery

3 IS:4722

Guide for rotating electrical machines

Batteries

The following table lists down the codes of practice for the maintenance of batteries −

General Requirements
Sr. No. Standards & Application
1 IS:1652

Guide for stationery cells and batteries, lead-acid type with plante positive plates

Cables

The following table lists down the codes of practice for the maintenance of cables −

General Requirements
Sr. No. Standards & Application
1 IS:1753

Aluminum conductors for insulated cables

2 IS:3961(part-2)

Guide for current ratings for cable

3 IS:3975

Guide for mild steel wires, strips and tapes for armouring cables

4 IS:5819

Guide for short circuit ratings of high voltage cables

5 IS:5831

Guide for PVC insulation and sheath of electric cables

Alternators

The following table lists down the codes of practice for the maintenance of alternators −

General Requirements
Sr. No. Standards & Application
1 IS:7132

Guide for testing synchronous machines

2 IS:5422

Guide for turbine type generators

3 IS:7306

Methods for determining synchronous machine quantities