Typical Cable Laying Details For Direct Buried, Low Tension Cables

Typical Cable Laying Detail For Direct Buried, Low Tension Cables
Most Construction projects requires underground cabling system for its power supply, some times High tension system too. The architects and builders are least bothered about how this cables routed to the premises and equipment. If electrical professionals pointed out the feasibility, the aesthetics of the project would touch to the intended level. Hence, in the planning stage itself the routes and size of the power cable trench to be incorporated in the project design.

Earthing or Grounding Method For Transformer Substation

Earthing or Grounding Method for Transformer Substation
MV switchgear and MV cables are to have separate main earthing bar connected to framework or earth bar of each item by insulated conductor and the earth-electrode by 2 insulated earthing conductors, one at each end of bar, via testing joints. Earthing conductor is to be minimum 150 mm2.

General Requirements for Electrical Earthing or Grounding System in Building Construction

General Requirements for Electrical Earthing or Grounding System in Building Construction
Component parts of earthing system are to include the following: Earth electrode (rods, tapes etc.); Main earthing terminals or bars; Earthing conductors; Protective conductors; Equipotential bonding conductors; Electrically independent earth electrodes for special systems (clean earth); Accessories and termination fittings, bonding, welding kits and other materials

Master Antenna TV System (MATV) In Electrical Construction Works

MATV System
Master Antenna Television or MATV means many TV connection outlets from one Master antenna control system. Usually high-rise apartment houses, hotels, schools and cluster based residential area utilizes this kind of TV distribution network. It may or may not include FM radio so that one outlet can receive both TV and FM reception. The scope of this section covers the design, supply, installation, testing and commissioning of Master Antenna TV System, for the reception and distribution of television broadcast signals.

Method of Electrical Earthing And Bonding Multicore Cables

Multicore Cable showing details of each parts

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.

Grounding or Earthing System In Electrical Construction Works

Grounding System In Electrical Construction Contract Works
The scope of work shall cover providing grounding stations, laying copper ground wires and connecting the panels, equipment, etc. to the ground grip as shown in the drawing. The ground station shall be as shown in the drawing. The ground electrode shall be minimum 10 feet long 1 inch dia steel pipe with copper weld exterior surface. The ground resistance shall be maintained with a suitable soil treatment as shown on drawings or as discussed and decided at site.

Typical Details For Cable Tray Installation And Support System

Typical Installation details for cable tray on walls
Below drawing shows how to install cable tray and its support system. This cable tray support system drawing has Isometric view and cross-sectional view. Following are the steps to be done for laying cables on wall mounted cable tray: Install cable tray support using a pre-fabricated flange or GI channel. The size, length and intervals of the support to be as per the specification, standards, number of cables, and size of the cable.

Method of Clean Earthing or Grounding in Electrical System

Representative image of Clean Earthing for Building Construction
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.

Earthing or Grounding Methods for Plant Rooms And Fixed Machinery

Earthing or Grounding Plant Rooms And Fixed Machinery

A. Main earthing bar or loop is to be conveniently located in electrical/mechanical plant rooms, and connected by earthing conductors to exposed conductive parts of motor control centre at its earthing bar, and to motors, switches and other electrical equipment etc. at their earthing terminals, using 20 x 2 mm insulated copper strips or 35 mm2 insulated copper conductor (minimum size) or as required to carry maximum earth fault current for 1 second with final conductor temperature not exceeding 200 deg. C (392 deg. F).

Conditions Of Sub-Contract Agreement In Construction

Sub-contract Agreement Form
Occasionally Main Contractor of the construction work depends sub-contractor for accomplishing some smaller or part of the project that may require specialized technical know-how and installation methods. In those cases Main contractor selects some sub-contractors who has capacity to achieve the task within the given time frame. Hence both of the parties, ie., Main contractor and Sub-contractor to be signed an agreement which protects both the parties' interest. Here is a sample for Conditions of Sub-contract Agreement in Construction Works.

Security and Access Control Systems (SACS) for Critical Security Areas

Security and Access Control Systems (SACS) for Critical Security Areas in A Building Project
Special areas like Airports, Port Trusts, Naval Base, Military base, Telecom buildings, Refinery, Petroleum handling areas etc. needed highly sophisticated security and access control system. It provides safety and security for both men and equipment the area handling. Here is the specification and installation methods for SACS.

Construction Specification For Electrical Busbar Trunking (Bus Duct) System

Busbar Trunking System
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.

Quality Plan for Construction Projects

Construction Quality Plan for Building Projects

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.

Mechanical, Electrical, Plumbing (MEP) in Construction Contract

MEP Works

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.

Importance of Fire Alarm System

Fire Alarm System block diagram
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 (LV) Switchgears in Electrical Construction Works

Low Voltage Switchgears in Electrical Construction Works

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.

 

Method of Earthing or Grounding for Diesel Generator Plant

Eletcric Generator (Image Credit: www.cummins.com)

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.