Tuesday, July 9, 2019

Digest - MCB Distribution Boards

Reading an electrical standard in full is a tedious job which most of us don’t relish. At the same time, familiarity with the provisions of the standard is essential for effective engineering practice. Considering this requirement, I am planning to publish digests of the relevant standards applicable to electrical equipment and switchgear. This will be a heavily condensed form of the standard but without missing the major points. It should also be kept in mind that this is no alternative to reading the standard itself. The number followed by the symbol # in brackets at the end of a sentence refers to the clause number in the standard.

MCB distribution boards are used to distribute electrical power to downstream loads. IS 13032:1991 (reaffirmed 2016) regulates the statutory attributes.

The following discussion is based on IS 13032:1991 (reaffirmed 2001)
  • MCB distribution board is defined as “An enclosure containing busbars and miniature circuit-breakers for the purposes of protecting, controlling or connecting more than one outgoing circuit fed from one or more incoming circuits. Miniature circuit-breaker boards are also known as miniature circuit-breaker distribution boards (MCB DB) or MCB boards (#3.1)  
  • The rated current of the MCB board is the rating of the busbars (#3.3)
  • Three types of MCB boards are defined. They are a) Single pole and neutral (SPN), b) Triple pole (TP), and c) Triple pole and neutral (TPN) (#5.1) 
  • The preferred number of outgoing circuits per phase are specified as 4, 6, 8, 12 and 16 (#5.2) 
  • The preferred rated voltages are 240 V and 415 V (#6.1) 
  • The preferred rated currents of the MCB outgoing ways shall be 6, 10, 16, 20, 25, 32, 40, 63, 80, 100 A (#6.2) 
  • The rated current of the busbar shall be 100 A or 200 A. The neutral busbar shall have the same rating as the phase busbar for the SPN MCB board. For TPN MCB boards, the neutral busbar shall be of the same rating as the phase busbar for boards up to and including 32 A and of half the rating as the phase busbars (subject to a minimum of 32 A) for boards having other ratings (#6.3) 
  • The manufacturer shall state the short time withstand capability of the board both in terms of the magnitude of the current and the duration of withstand. Unless otherwise specified, the time of withstand shall not be less than 0.1 second. The magnitude of the current shall be at least equal to that of the MCB incorporated in the board having the highest category of duty (#6.6) 
  • Routine tests are intended to detect faults in materials and workmanship. They are carried out on every new MCB board after its assembly or on each transport unit. Another routine test at the place of installation is not required (#9.1.2) 
  • Routine tests include a) routine tests on MCBs as the case may be, b) Inspection of the board including inspection of wiring, and if necessary, electrical operation test, c) dielectric test and d) Checking of protective measures (#9.1.2)

Saturday, October 1, 2016

Important Provisions in the Electricity Act 2003 & CEA Regulations 2010

Important Provisions in the Electricity Act 2003 & CEA Regulations 2010

Reference Rule / Section
Qualification of Electrical Inspector
The Electricity Act 2003, Section 162
Appointment of Electrical Inspector
The Electricity Act 2003, Section 162
Powers and functions of Electrical Inspectors Under the Electricity Act 2003
The Electricity Act 2003, Section 162
Electrical Accidents
The Electricity Act 2003, Section 161
Approval by Electrical Inspectors
R 32, 36, 43, 52, 54, 63,
The Electricity Act 2003, Section - 54
Clearance of conductors above ground level for buildings etc.
R 58, 59, 60, 61, 62, 63, 65, 66, 67, 68,  69, 71, 73
Notice for power shut down and precaution against failure of supply
R 39

Note: - The term "R" appears in this document stands for "Regulation' of Central Electricity Authority (Measures Relating to Safety and Electric Supply) Regulation 2010.

Friday, September 30, 2016

The Electricity Act, 2003

Relevant Sections in connection with powers and appointment of Electrical Inspector

21. "Electrical Inspector" means a person appointed as such by the Appropriate Government under sub section (1) of section 162 and also includes Chief Electrical Inspector;

53. (1) The Authority may in consultation with the State Government, specify suitable measures for -
 (a) protecting the public (including the persons engaged in the generation, transmission or distribution or trading) from dangers arising from the generation, transmissions or distribution or trading of electricity, or use of electricity supplied or installation, maintenance or use of any electric line or electrical plant;
(b) eliminating or reducing the risks of personal injury to any person, or damage to property of any person or interference with use of such property;
(c) prohibiting the supply or transmission of electricity except by means of a system which conforms to the specification as may be specified;
(d) giving notice in the specified form to the Appropriate Commission and the Electrical Inspector, of accidents and failures of supplies or transmissions of electricity;
(e) keeping by a generating company or licensee the maps, plans and sections relating to supply or transmission of electricity;
(f) inspection of maps, plans and sections by any person authorized by it or by Electrical Inspector or by any person on payment of specified fee;
(g) specifying action to be taken in relation to any electric line or electrical plant, or any electrical appliance under the control of a consumer for the purpose of eliminating or reducing a risk of personal injury or damage to property or interference with its use;

54. (1) Save as otherwise exempted under this Act, no person other than Central Transmission Utility or a State Transmission Utility or a licensee shall transmit or use electricity at a rate exceeding two hundred and fifty watts and one hundred volts –

(a) in any street; or
(b) in any place;

(i) in which one hundred or more persons are ordinarily likely to be assembled; or
(ii) which is a factory within the meaning of the Factories Act, 1948 or a mine within the meaning of the Mines Act, 1952; or
(iii) to which the State Government, by general or special order, declares the provisions of this sub-section to apply,
without giving, before the commencement of transmission or use of electricity, not less than seven day's notice in writing of his intention to the Electrical Inspector and to the District Magistrate, or the Commissioner of Police, as the case may be, containing particulars of the electrical installation and plant, if any, the nature and the purpose of supply and complying with such of the provisions of Part XI of this Act, as may be applicable:

Provided that nothing in this section shall apply to electricity used for the public carriage of passengers, animals or goods, on, or for the lighting or ventilation of the rolling stock of any railway or tramway subject to the provisions of the Railways Act, 1989.

151. No court shall take cognizance of an offence punishable under this Act except upon a complaint in writing made by Appropriate Government or Appropriate Commission or any of their officer authorized by them or a Chief Electrical Inspector or an Electrical Inspector or licensee or the generating company, as the case may be, for this purpose.

161. (1) If any accident occurs in connection with the generation, transmission, distribution, supply or use of electricity in or in connection with, any part of the electric lines or electrical plant of any person and the accident results or is likely to have resulted in loss of human or animal life or in any injury to a human being or an animal, such person shall give notice of the occurrence and of any such loss or injury actually caused by the accident, in such form and within such times as may be prescribed, to the Electrical inspector or such other person as aforesaid and to such other authorities as the Appropriate Government may by general or special order, direct.

(2) The Appropriate Government may, if it thinks fit, require any Electrical Inspector, or any other person appointed by it in this behalf, to inquire and report -

(a) as to the cause of any accident affecting the safety of the public, which may have been occasioned by or in connection with, the generation, transmission, distribution, supply or use of electricity, or
(b) as to the manner in, and extent to, which the provisions of this act or rules and regulations made there under or of any license, so far as those provisions affect the safety of any person, have been complied with.

(3) Every Electrical Inspector or other person holding an inquiry under sub-section (2) shall have all the powers of a civil court under the Code of Civil Procedure, 1908 for the purpose of enforcing the attendance of witnesses and compelling the production of documents and material objects, and every person required by an Electrical Inspector be legally bound to do so within the meaning of section 176 of the Indian Penal Code.

162. (1) The Appropriate Government may, by notification, appoint duly qualified persons to be Chief Electrical Inspector or Electrical Inspectors and every such Inspector so appointed shall exercise the powers and perform the functions of a Chief Electrical Inspector or an Electrical Inspector under this Act and exercise such other powers and perform such other functions as may be prescribed within such areas or in respect of such class of works and electric installations and subject to such restrictions as the Appropriate Government may direct,

(2) In the absence of express provision to the contrary in this Act, or any rule made there under, an appeal shall lie from the decision of a Chief Electrical Inspector or an Electrical Inspector to the Appropriate Government or if the Appropriate Government, by general or special order so directs, to an Appropriate Commission

Important facts and figures:

The Electricity Bill, 2001 was introduced in Lok Sabha on 30th August 2001 and was subsequently referred to the Standing Committee on Energy for examination and report. The Standing Committee submitted its report on 19th December 2002 Based on the recommendations of the Standing Committee on Energy, the Government of India moved certain amendments. Lok Sabha passed the Electricity Bill, 2001 along with these amendments, on 9th April 2003.

The Bill as passed by Lok Sabha was considered and passed by Rajya Sabha on 5th May, 2003.

The Electricity Bill 2003 as passed by both Houses of the Parliament received President's assent on 26th May 2003 and was notified in the Gazette of India on 2nd June 2003.

The provisions of the Act except section 121 were brought into force with effect from 10th  June 2003.

Background and salient features of the Act:

The Act strikes a balance, which takes into account the complex ground realities of the power sector in India with its intractable problems. The salient features of the Act are;

(i)            The Central Government to prepare a National Electricity Policy in consultation with State Governments. (Section 3)
(ii)           Thrust to complete the rural electrification and provide for management of rural distribution by Panchayats, Co-operative Societies, Non-Government organizations, franchisees etc. (Sections 4,5 & 6)
(iii)          Provision for license free generation distribution in the rural areas. (Section 14)
(iv)         Generation being de-licensed and captive generation being freely permitted. Hydro projects would, however, need clearance from the Central Electricity Authority. (Sections 7, 8 & 9)
(v)          Transmission Utility at the Central as well as State level, to be a Government company - with responsibility for planned and coordinated development of transmission network. (Sections 38 & 39)
(vi)         Provision for private licensees in transmission and entry in distribution through an independent network. (Section 14)
(vii)        Open access in transmission from the outset. (Sections 38-40)
(viii)       Open access in distribution to be introduced in phases with surcharge for current level of cross subsidy to be gradually phased out along with cross subsidies and obligation to supply. SERCs (State Electricity Regulatory Commission) to frame regulations within one year regarding phasing of open access. (Section 42)
(ix)         Distribution licensees would be free to undertake generation and generating companies would be free to take up distribution businesses. (Sections 7,12)
(x)          The SERC (State Electricity Regulatory Commission) is a mandatory requirement. (Section 82)
(xi)         Provision for payment of subsidy through budget, (Section 65)
(xii)        Trading, a distinct activity is being recognized with the safeguard of the Regulatory Commissions being authorized to fix ceilings on trading margins, if necessary. (Sections 12, 79 & 86)
(xiii)       Provision for reorganization or continuance of SEBs (State Electricity Boards). (Sections 131 & 172)
(xiv)       Metering of all electricity supplied made mandatory. (Section 55)
(xv)        An Appellate Tribunal to hear appeals against the decision of the CERC (Central Electricity Regulatory Commission) and SERCs (State Electricity Regulatory Commission). (Section 111)
(xvi)       Provisions relating to theft of electricity made more stringent. (Section 135-150)
(xvii)      Provisions safeguarding consumer interests. (Sections 57-59, 166) Ombudsman scheme (Section 42) for consumers' grievance redressal.