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.
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.
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.
Vacuum Interrupter (VI) are vacuum sealed-off devices incorporated in Vacuum Circuit Breakers (VCB) to cause interruption of fault currents in medium voltage electrical distribution systems. The contacts of the VI are pressed against each other under normal circuit conditions. In the event of a fault current, the VCB mechanism effects withdrawal of the movable contact from the fixed contact.
Comply with the General Conditions, Supplementary Conditions and the requirements in various Sections of the Electrical Specification. In addition read and conform to all Electrical Sections of these specifications. The installation shall comprise air networks connected to roof and down conductors and finally terminated in earth electrodes, via structural re-bars and suitable test points in accordance with the details included on the attached drawings or in the Specification Section.
Construction companies normally submit Payment application every month as per the contract agreement. Until completion of the project, they get part payment from their client after submission of claim which is duly approved and certified by project consultant. Project QS collect all the relevant work details and progress percentage from the field engineers in close coordination with Project Manager.
First of all, we have to look into what is the definition of Appliance in-general and specifically for Electric Appliance.
Definition of 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.....
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.
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.
Every project is unique, in particular, construction projects. There are many methods applied to accomplish functioning of individual installations included in the whole project. Building services like Mechanical, Electric, and Plumbing (MEP) work have given more importance than other disciplines dealt with. It's because of complexity and alternate methods available to accomplish the same output. While executing individual installations - also known as tasks - construction team have to adopt suitable methods submitted as an integral part of Tender. Most of the project managers or representatives of client keen to look Method Statement of critical and important tasks. We will look into what is Method Statement and what is the importance a Method Statement brings to a construction project.
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.
Earth / Ground Station
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.
The resistance of each ground shall not exceed 2 ohms.
The ground wire shall be fixed to the rod with a clamp and safety set screws. The clamp shall be permanently accessible. Manholes with proper covers shall be provided.
Ground connections shall be of the bolted type on the top of the rod.
In electrical projects, both construction as well as maintenance, the following terms used on the Drawings, Specifications and in the actual Work site are equivalent and may be used interchangeably: "earth" and "ground"; "earthing" and "grounding". Besides, this article tries to rectify misinterpretation of some important terms often used by people involved in the electrical earthing / grounding work.
Reliable electrical power becomes one of the most wanted factor in modern world industry where operation should be uninterruptible and maximize the cycle of operation, output quality and to avoid losses and damages. Here we are talking about Automatic Transfer Switches (ATS) also known as Automatic Mains Failure (AMF) panel to cater uninterrupted power supply from Mains or backup sources like Diesel gen-set, static ups etc.
What is Automatic Transfer Switch (ATS)?Automatic Transfer Switch (ATS) is an automated switching device that transfers load power to backup power during mains failure and back to its original state when mains power reinstate to the normal condition. It will have its own contacts, microprocessor to analyses the conditions whether power supply is normal or backup and need backup or mains power. Here "back up power" may become either Standby generator or another mains power or static power source like UPS.