In this sample MEP specification section, Mechanical Ductwork, Grilles And Diffusers have been described in detail under construction contract work.

Main Highlights of this MEP Specification

1. Mechanical Ductwork
2. Mechanical Ductwork Supports
3. Mechanical Dampers - General Requirements
4. Flexible Joints for Mechanical Ductwork
5. Air Intakes and Outlets
6. Kitchen Extract Canopies
7. Kitchen Extract Air Ductwork
8. Access Doors
9. Ductwork Test Points
10. Ductwork Protection
11. Grilles
12. Diffusers
13. Sand Trap Louvres
14. Air Valves
15. Fire Dampers

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.

At the completion of the electrical installation works, the entire installation shall be subject to the test before final placing in service under the full responsibility of the contractor. Unless Otherwise specifically called for all tests shall be carried out in conformity with IEE regulations. Contractor shall coordinate with the Client and the Supervising Engineer to get electricity from the local supply authority before starting of testing and commissioning.

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.

Method Statement For Installation Of Galvanized Conduits that has to be installed on the Exposed Surface of a building is described here.

1. Introduction and Scope

This method of statement specify the detailed requirements and procedures for the installation of Galvanized Conduits for the exposed surface installation requirement for MEP services of the above building.

1. Introduction and Scope

This method of statement specifies the detailed requirements and procedures for the installation of Power and Lighting System Wiring.

2. Applicable Project Specification

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.

The work included within this section is for the supply, connection, testing and commissioning of 13.8 KV switch gears, cables, package sub station and all the related accessories necessary for the proper operation of the system as shown and described on drawings, bill of quantity and herein.

The contractor shall coordinate with the other services (trades) involved in the project to insure that the foundation, are suitable for the equipment to be installed.

The Contractor shall design, supply and install outlet plates, conduits, trunking, trays, wiring, junction boxes, distribution frames, patch panels, data rack, backbone cables, etc. necessary to form a complete structured system for voice and data cabling within the buildings. Cabling / wiring shall be provided for voice system from patch panel location to each voice/data outlet. Draw wires shall be provided in conduits for future data cabling / wiring by others (if applicable). The installation shall comply with the requirements of ANSI / EIA / TIA-568-1991 as appropriate as well as Local Telecom Authority.

Voice and data outlet plates shall be designed to accept industry standard RJ45 plugs.

The DC power supply shall consist of batteries and batteries charger.

Batteries of DC Power Supply - Technical Specifications

The batteries shall be nickel cadmium type with pocket plates type range TP, T.

Buried Earth Conductors:

PVC insulated copper strip conductors or PVC insulated stranded copper cables with cross-section min 70 mm2 or as per earthing calculation.

Earthing Conductors:

PVC insulated copper conductor as described in the Specification for the particular application.

Building projects requires MV Distribution Panel Boards for distribution of power to each utilities. A good electrical distribution network will have proper design, right components, and future load provisions. Space utilization will also be an important factor for maintenance and handling of the equipment. Here we look into what are the features required for design, manufacture, install a MV Distribution panel board including its BIS (IS) standards that serving quality building projects.

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).

This article covers the manufacture, supply, installation, testing and commissioning of 415 volts, 3 ph, 4 wire, Diesel Alternator Set (Diesel Genset). The set shall be mounted on common base frame and complete in all respects including the auxiliary equipment such as battery auxiliary, lube oil pumps, filters, oil storage tank, centrifuge, etc. including piping required for interconnection between the set and the auxiliaries which are mounted separately.

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.

Compound Demarcation or separations of compounds may use metallic fences sometimes for saving money or aesthetic reasons. Architects and owner of the project decide whether their property protected by compound wall or it needs only fencing. If fencing considered, most cases it will be metallic fence. In the electrical point of view and as a safety measure, metallic fence shall be separately earthed unless they come within 1.8 m of any equipment or structure above the surface of the ground, which is connected to the main earthing system. If the separation of 1.8 m cannot be obtained the fence shall be bonded to the earthing system. Here is how compound fences connecting to the earthing system.

These drawings show how to install Fire Alarm Break Glass (BG) or Manual Call Point (MCP) on walls. It has to be mounted on back box installed in the wall. This box (embedded or exposed as specified in the concerned section of the specification) has to be connected through GI / PVC conduit that will have the Firetuff or equivalent cable to be looped for other detectors. Conduit end to be taken out of the wall above false ceiling to allow the Firetuff cable to be clipped on soffit of the slab.

Drawing below shows how to install Manual call point break glass along with a sounder

In this typical drawing, manual call point break glass unit has been shown as concealed  and the rest  are surface installed in the false ceiling. Sounder has been mounted on ceiling but can also be mounted on wall visibly as per the project specification.

Audio Intercom System being used in high-rise buildings or commercial complexes, provide two way communication from entrances, gates, go-downs, industrial plant rooms and normal doors, to an internal audio handset. It can be used to screen authorized visitors from outside entrance and useful to communicate internally between persons from one room to another room or office spaces. It can also be used to function as effective public announcement system.