J A V A D IUS B O L L A H ELECTRICAL MAINTENANCE & REPAIR KOTA KINABALU 2 0 2 1
ELECTRICAL MAINTENANCE & REPAIR
Published by: POLITEKNIK KOTA KINABALU No.4, Jln Politeknik, KKIP Barat, Kota Kinabalu Indsutrial Park, 88460, Kota Kinabalu, Sabah. Tel: 088-401800 Fax: 088-499960 web: https://polikk.mypolycc.edu.my Hak cipta terpelihara. Tidak dibenar mengeluar ulang mana-mana bahagian artikel, illustrasi dan isi kandungan buku ini dalam apa jua bentuk dan dengan apa cara sekalipun, sama ada secara elektronik, fotokopi, mekanik, rakaman atau cara lain sebelum mendapat izin bertulis daripada Politeknik Kota Kinabalu.
Preface ELECTRICAL MAINTENANCE & REPAIR is a course that teaches students about the methods used in the maintenance and repair of electrical equipment. It places a greater emphasis on the upkeep of electric-powered equipment. It also demonstrates knowledge and comprehension of electrical schematic diagrams, as well as adherence to all safety protocols, rules, and good practises. We may avoid costly and harmful situations by performing routine electrical maintenance. Electrical wiring, for example, is not always in your face for you to monitor. You're not going to pass past your cables and notice a frayed wire with a worn housing (well, we hope not as they should be neatly tucked away). You will be able to pick up these items and have them repaired straight quickly, before they begin to damage the rest of your family, such as your lighting and charging devices, thanks to these checks.
1 2 3 4 C O N T E N T : T A B L E O F Maintenance Maintenance of Electrical Distribution System Equipment Maintenance Other Equipment EDISI POLITEKNIK MALAYSIA
Author Ts. Javadius Bollah is an Electrical Maintenance & Repair author. He worked as a senior lecturer at Politeknik Kota Kinabalu for nearly 20 years. This is his first E-book for the year 2021, and he plans to continue contributing to the writing of another book in the coming years. He has a bunch of teaching expertise in the field of electrical engineering especially in electrical maintenance, electrical installation, dc and ac motor and power electrical protection.
Be familiar with the fundamental concepts of electricity. Be familiar with the effects of electricity on the human body. Be able to recognize common electrical hazards. Be familiar with electrical protective devices OBJECTIVE OF MAINTENANCE CHAPTER 1 MAINTENANCE
Safety working environment and operation of electrical installations Safety use of electricity & electrical equipment Safety of working personnel-electrical technical person and workers Safety standards of electrical installations & equipment IMPORTANCE OF ELECTRICAL SAFETY
TYPES OF ELECTRICAL INJURIES Electrocution is death or severe injury by electric shock, electric current passing through the body. The word is derived from "electro" and "execution", but it is also used for accidental death. Electrocution (death due to electrical shock) Faulty appliances Damaged or frayed cords or extension leads Electrical appliances in contact with water Incorrect,damaged or deteriorated household wiring Downed power-lines Lightning strike Some causes of electric shock are:
1.3 TYPES OF ELECTRICAL INJURIES Burns Heating due to resistance can cause extensive and deep burns. When applied to the hand, electricity can cause involuntary muscle contraction, producing the "no-let-go" phenomenon, and increasing the risk for serious burns Voltage levels of 500 to 1000 volts tend to cause internal burns due to the large energy (which is proportional to the duration multiplied by the square of the voltage divided by resistance) available from the source.
TYPES OF ELECTRICAL INJURIES Safety tips to reduce the risk of electric shock:- Do not use extension leads or appliances if the cords are damaged or frayed. Throw them away if they are damaged in any way. Do not remove a plug from a power point by pulling on the cord – pull the plug instead. Electric shock may cause muscles to contract causing a worker to lose his or her balance and fall. An explosion from an electrical incident can also cause a fall. source: https://torangene.com/first-aid/first-aid-for-electricshock/
Safety tips to reduce the risk of electric shock:- Keep electrical appliances away from wet areas. Electricity and water don’t mix. Wear rubber or plastic soled shoes when using electrical appliances, especially in wet areas, on concrete or outdoors. Have safety switches installed by an electrician.
TYPES OF ELECTRICAL INJURIES Falls due to electrical shock Falls happen when a heavy equipment operator experiences a low-voltage shock that causes them to fall from the ladder or machinery. The loss of balance and disorientation can lead to cardiac arrest, a low-voltage injury, or death. https://www.oreskylaw.com/what-to-do-after-electrical-shock-accidents/
ELECTRIC SHOCK EFFECT https://www.oreskylaw.com/what-to-do-after-electrical-shock-accidents/ If electrical systems are not properly wired to remove dangerous voltage, persons can be subjected to electric shock, which can result in injury or death. People become injured and death occurs when voltage pushes electrons through the human body, particularly through the heart. An electrical shock from as little as 50V alternating current for as little as one second can disrupt the hearts rhythm resulting in death in a matter of minutes from ventricular fibrillation.
https://www.oreskylaw.com/what-to-do-after-electrical-shock-accidents/ What determines the severity of electric shock? The severity of an electric shock is dependent on the current flowing through the body, which is impacted by the electromotive force (E) measured in volts and the contact resistance (R) measured in ohms, using the formula is I = E/R. To protect against electric shock from dangerous voltages on metal parts of electrical equipment from a ground-fault must be quickly removed by opening the circuit’s overcurrent protection device.
Electricity Regulation 1994 Definition Contractors shall make them thoroughly conversant and confrom to the Electricty Supply Act 1990, Electricity Regulations 1994, IEE regulation and TNB Electrical Safety Rules governing any work they may have to undertake in any electrical installation or system. Work must be carried out by competent personnel only.
Electricity Regulation 1994 Definition Regulation 110 Inspection and test for the purpose of maintenance of installation, etc. (1) An installation shall be maintained in good and working order and safety precautions shall be observed at all times to prevent danger. (2) The responsibility to maintain the installation in the manner required in sub regulation (1) shall be with the owner, management, licensee or occupier of the installation, his servant or agent ,as the case may be.
Electricity Regulation 1994 Definition Regulation 110 Inspection and test for the purpose of maintenance of installation, etc. (3) An installation, other than a domestic installation, shall be checked and tested by a competent person at least once in every five years, or at any time as directed by the Commission. (4) Any protective relay and device of an installation shall be checked, tested and calibrated by a competent person at least once in every two years, or at any time as directed by the Commission.
Electricity Regulation 1994 Definition Regulation 110 Inspection and test for the purpose of maintenance of installation, etc. (5) The Commission may inspect an installation or the premises where an installation is located if the Commission thinks it is desirable to do so in the interest of the publicor for public safety and if a notice in writing is given to the owner, management or licensee of an installation or any premises, the owner, management or licensee of the installation orpremises, as the case may be, shall cause the person in charge of the installation or premises to attend and give such assistance as may be ordered by the Commission in the notice.
Electricity Regulation 1994 Definition Regulation 111 Competent person to undertake maintenance work. No person, except a competent person or a person acting under the control of a competent person, shall undertake to carry out any repair, replacement, servicing or cleaning of any equipment which forms part of an installation.
Electricity Regulation 1994 Definition Regulation 112 Adequate safety precautions to be taken during work. (1) A competent person shall take adequate precautions to prevent any installation or equipment from being accidentally or inadvertently made a live when persons are working. (2) Any person engaged in work in connection with any installation or equipment shall be adequately protected from danger, and the responsibility for such protection shall be on the licensee or supply authority, owner, management or occupier of the installation, his servant or agent, as the case maybe.
Electricity Regulation 1994 Definition Regulation 112 Adequate safety precautions to be taken during work. (3) Where any person is engaged in work on a circuit controlled by a switch not under his immediate supervision, the switch shall be locked in "OFF" position until the work is finished and— (a) in the case of aerial line work, a notice shall be hung on the switch and earthing sticks to provide earthing shall be fixed at a visible distance from the workmen; and (b) in the case of underground cabling work, a suitable notice shall be hung on the switch, to warn any person that there are persons at work on the circuit and that the switch shall not be closed.
Electricity Regulation 1994 Definition Regulation 112 Adequate safety precautions to be taken during work. (4) If the circuit is operated at high voltage or extra high voltage, the switch in subregulation (3) shall be locked in the "OFF" position by the competent person. (5) No competent person or person under the control of a competent person shall reclose any switch until he is certain that all persons are clear of the circuit concerned and have been warned that the circuit is to be made alive.
Electricity Regulation 1994 Definition Regulation 112 Adequate safety precautions to be taken during work. (6) No person shall defeat, remove or damage a safety device fitted in connection with or for use with any installation or equipment. (7) Not with standing sub-regulations (1),(3),(4) and (5), where the competent person is satisfied that live work on any installation, equipment or circuit, as the case may be, is safe, it shall not be unlawful for any person to engage in such work.
Electricity Regulation 1994 Definition Regulation 113 Competent person to issue written instruction. No work or operation under the control of a competent person shall be commenced until a written instruction has been issued by the competent person
Don’t directly touch the person who is still in contact with live conductor. SAFETY PRECAUTIONS TO AVOID ELECTRICAL ACCIDENTS
SAFETY PRECAUTIONS TO AVOID ELECTRICAL ACCIDENTS Grounding Insulation strength For Live wire connection
Plug point disconnection. (when unused) SAFETY PRECAUTIONS TO AVOID ELECTRICAL ACCIDENTS Install switches-to avoid open, unprotected ends of wire.
Use fuses & other protective devices to avoid damage to the equipment. Wear a proper attire during working. SAFETY PRECAUTIONS TO AVOID ELECTRICAL ACCIDENTS