This method of statement specifies the detailed requirements and procedures for the installation of Power and Lighting System Wiring.
Section: Cables and wiring
Division: Installation
Sub Division: Subdivision
Clean earth grounding or low noise earth shall be provided as required, to ensure that the level of induced or conducted interference from external sources, including the facility power grounding system, does not produce incidence of malfunction of the equipment, which is unacceptable for the operating system. The electronics systems must be protected by providing a network path having low impedance for interconnecting its equipment.
Proper routing, zoning and shielding of the cables / earth wires are important and must serve the purpose of preventing sources of electrical disturbances from the operation of electrical equipment.
Most electronic systems which are responsible for modern advances are based on digital technology. All digital systems, computers and microprocessors are assembled from simple circuits called logic circuits. The basic building blocks of logic circuits are logic gates. And logic gates themselves are simple electronic circuits comprising of diodes, transistors and resistors.
Component parts of earthing system are to include the following:
Continuity: Ensure that complete earthing system is electrically continuous and mechanically secure. Locations of main earth bars in substations, electrical rooms, mechanical rooms, hub (Technical) rooms, etc., to be clearly identified by 100mm X 100mm white traffolyte labels, with red lettering, to Engineer's approval.
Busbar Trunking System (BBT) in electrical construction, uses to transporting electrical power to a shorter distance but many utilization point, say, within the building or a compound of facilities. Though cables can also be used in these areas, their economic impact would be high if compared to the effective Busbar Trunking System. It will help us to tap power directly from where we want it to be and make utilize to the service point.
This specification intended to supply, install, test and commission mineral oil immersed 1500 KVA, 3 phase indoor transformers, fitted with cable boxes, bolts, and all necessary accessories. Transformers shall be indoor type, oil filled, two winding, four off load capacity, 2.5% taps, two above and two below high voltage rating in compliance with IEC 76 or BS 171.
Electrical engineering deals with practical applications involving current flow through conductors; focuses on the design, construction, and operation of electrical systems and equipment. It includes developing, producing and testing of electrical and electronic devices and equipment, such as, generators to produce and distribute electricity, electric motors and other electrical machinery, transmission line.
The acronym MEP became an integral word of a building project in Middle East Gulf region during year 2000. In the inception stage of MEP, there were involvement of only two engineering branches, Mechanical and Electrical, now it included electronics, instrumentation and communication. In some occasions, Mechatronics also partake in the project for smooth completion of the whole MEP works. Companies that carry out MEP works also known as Electro-Mechanical company which has multi-faceted technicians and engineers for effective design, coordination and execution of the works.
Fire Alarm System installation work covered by this section of the specifications includes the furnishing of all labor, equipment, materials, and performance of all operations in connection with the whole Fire Alarm System as shown on the drawings and as herein specified. The requirements of the conditions of the Contract, Supplementary Conditions and General Requirements apply to the work specified in this section.
The metallic sheath and armour of multicore cables shall be bonded together and earthed.
Cable earthing conductors shall be copper strip with appropriate section laid in formed cable trenches or ducts, or fixed to walls, concrete or steel work, by means of clamps or claw type cleats, appropriately secured into suitable wall plugs or tapped holes. The spacing of fixings shall not be greater than 1 m. Where earth strip is buried or laid in positions in which there is danger of corrosion it shall be provided with a corrosion-proof serving of extruded thermo-plastic or self-adhesive PVC tape which for short lengths may be hand applied on Site.
We often depends Diesel Electrical Genset as emergency power system due to mains failure. As a professional, the installation of diesel electrical power generator should be as per the clients requirement and to be inline with the authoritative norms and standards. Safety, security, convenience, future expansions etc are to be considered and co-ordinated before start detailing of the genset's installation. The generator should be as close to the main change-over board as possible. In cases like Textile Mills, where there is fear of smoke affecting the quality of the yarn etc., generators may be located away from the Plant / Department.
In this sample MEP specification section, Mechanical Ductwork, Grilles And Diffusers have been described in detail under construction contract work.
It is essential that services and systems in a building construction contract work are provided to conform to the requirements of the customer, and that the activities be effected as economically as practical. The achievement of these objectives is facilitated by setting up working procedures and practices, which collectively provide a “Work Efficient”, yet controlled operating environment. It is the purpose of this Construction Quality Plan to give instruction to personnel, on the implementation of the company system such that the above objectives are accomplished. Documentation specific to the project will be provided to ensure full compliance with the particular requirements of the contract.
First of all, we have to look into what is the definition of Appliance in-general and specifically for Electric Appliance.
What is the definition of Appliance? The term appliance can be defined as, "a device or apparatus or equipment designed to perform an application or task, other than industrial, benefited in our personal life that uses some kind of technology". In short, an appliance is a machine that reduces a human’s effort in carrying out a specified work or task. For example, a scissor uses to cut our hair, an iron box to ironing our clothes, a TV to watch entertainment programs and news form different parts of the world. Here, scissor uses mechanical technology to perform its function. It uses only mechanical energy that generated by parson it operates, where as, other two appliances use electricity as the source of energy to operate it. Appliances may be indoors or outdoors, fixed or portable or hand held or hand operated or remotely operated or computer controlled and there on.....
Fire alarm systems have become increasingly sophisticated and functionally more capable and reliable in recent years. They are designed to fulfill two general requirements: protection of property and assets and protection of life. As a result of state and local codes, the life-safety aspect of fire protection has become a major factor in the last two decades.
Low Voltage Switchgear are familiar to every people since they are the controlling mediators between low voltage utilities and equipment with human beings. Be it a common home DB or an isolator or control centres, they all are being manufactured to use untrained people ie., common people. The scope of works shall cover the supply installation, testing and commissioning of main and sub-distribution boards, panel boards, fusible safety switches, circuit breakers etc. Associated minor building works require for the erection of the distribution boards and panels shall be included in the scope of work.
Earthing or Grounding of Diesel Generator Plant is important to ensure correct operation of the plant and safety of the people who work over there. Generator neutral (star point) is to be connected by insulated earthing conductor through the neutral earthing link or device to main earthing bar. Neutral earthing conductor is to be suitably sized to carry maximum earth fault current for time it takes the system protection to operate with final conductor temperature not exceeding 160 deg. C, but not less than 30 mm2 per 100 kVA of generator rating, with a minimum of 50 mm2. All emergency power diesel gensets including portable gensets to be connected to grounding conductor.
Also read: Guidelines for installing emergency power diesel genset.
Earth electrode resistance, Insulation resistance of factory-built materials installed at the site and Insulation resistance of site-built materials installed at site to be considered individually for field quality control check. It is further to be monitored earth resistance of individual earth unit and combined resistance of earth units.
Construction projects highly depends on typical installation details and drawings. Architects and engineers use this kind of information to reduce their work load. Employees particularly technicians and foremen who execute the project uses typical drawings as general guidelines where repeated structure, forms, shapes, operations, loads, etc. come into force.