BEDROOM LIGHTING

BEDROOM LIGHTING

The bare minimum

The following is an outline of basic requirements for a three-bedroom house with 120m2 floor area. This would be a typical speculative estate development.

* Rooms: small kitchen; dining room; lounge; downstairs cloakroom; main bedroom with en-suite bathroom; second double bedroom; small single bedroom; landing bathroom or shower room; 

*Heating: central heating by gas or oil; 

*Garden: small garden at both front and rear.

Standards

National House Building Council (NHBC)

The NHBC give minimum standards for living accommodation and services, which are shown in It should be noted that houses vary in size and use, so the values given should be considered as a minimum.

Relevant wiring regulations

13 A socket-outlets

* Building Regulations now require socket-outlets, wall switches and other similar accessories to be sited in habitable rooms at appropriate heights of between 450 and 1200mm from the finished floor levels. 

*Any socket-outlet with a rated current not exceeding 20 A, which is used by ordinary persons’ equipment for use outdoors must be provided with additional protection by means of a 30mA RCD.

*No 230V sockets, except shaver sockets complying with BS EN 61558-2 are permissible in bathrooms and shower rooms.

* 230V socket-outlets must be located at least 3m outside the boundary of zone 1 and provided with 30mA RCD protection.

Lighting

*To avoid danger and inconvenience, there should be more than one lighting circuit. 

* In a bathroom, all equipment must be suitable for the zone in which it is installed. 

*Wall switches and other accessories must not be installed in zones 0, 1 and 2. 

* Cord switches must be installed outside of zones 0, 1 and 2, but the cord may hang within zones 1 and 2.

*There are restrictions on the current-using equipment in zones 0, 1 and 2. 

* Equipment that is installed in zones 1 and 2 must have water penetration protection of at least IPX4.

*A careful study of BS 7671: 2008 Section 701 is recommended.

Three Bedroom House Wiring

 Three Bedroom House

At one time, domestic electrical installations were simple and only basic design planning was necessary. A good electrician could be sent on site with a van load of wiring materials, and with no written instructions or drawings. The installation arrangements were rule-of-thumb and the quality of the job depended on the craftsmanship of the operative.

Any special requirements or missing information could be negotiated on site. Costing was repetitive and easy. The contract price was a simple multiple of the number of lights and sockets. Times have changed. There is probably no such thing as an average householder. Most occupiers have specialist requirements based upon the choice of room utilisation, decor, hobbies and the activities of the various residents.

It is not easy for an architect to forecast the furniture layout in a room. A modern speculative electrical installation cannot make universal provision for every conceivable arrangement. Most publications offering guidance on the requirements of BS 7671 (the Wiring Regulations) will often recommend that a project should be discussed with the client. This is essential for a custom-built house. As an alternative, the installation could incorporate some design flexibility, so that the new family is not restricted to bed positions or where kitchen equipment may be plugged in.

Standards for the house industry are determined by the National House Building Council (NHBC). Most building societies and other mortgage lenders require compliance with NHBC requirements.

This blog starts by illustrating a basic, cost-conscious electrical installation. A scheme may be lifted straight from the pages for such a contract. For more advanced schemes, it is hoped that developers will be enticed into better electrical facilities with a ‘modern living’ theme. A good quotation will include optional extras for improved lighting and socket-outlet facilities. Not all house purchasers want the cheapest possible electrical installation.

Operation of Hydro Power

 Operation of Hydro Power

The operation of micro-hydro power plants is intended not only to generate electric power by rotating generators but also to control generation equipment and to supply electricity of stable quality to consumers, keeping good condition of all facilities related.

Since facilities and equipment installed depend on site conditions and budget, there are various ways of operation for micro hydro. In case of a plant that has an automatic load stabilizer, the operators do not always have to control equipment except in cases of starting, stopping and emergency. Furthermore, in cases where an automatic stopping system and recording system are installed, operators do not always have to stay in the power plant.

In many cases of micro hydro for rural electrification, however, automatic control system and protection equipment are often omitted because of budget limitations.

Therefore, in general, operators always should stay in the power plant to control equipment or be prepared to rush to the plant in order to immediately take measures in case of trouble.

History Of Electricity

 Benjamin Franklin is famous for his discovery of electricity.

He started studying electricity in the early 1750s. His observations, including his kite experimentation, verified the nature of electricity. He knew that lightning was very powerful and hazardous. The famous 1752 kite experiment featured a pointed metal bit on the top of the kite and a metal key at the base end of the kite row. The row went through the key and attached to a Leyden Jar. (A Leyden jar consists of two metal conductors separated by an insulator.)

He held the row with a short section of dry silk as insulation from the lightning energy. He flew the kite in a thunderstorm. He initially noticed that various loose strands of the hemp row stood erect, avoiding one another. (Hemp is a perennial American plant used in rope making by the indians.) He proceeded to feel the key with his knuckle and received a little electrical shock.

Between 1750 and 1850 there were many great discoveries in the principles of electricity and magnetism by Volta, Coulomb, Gauss, Henry, Faraday, and others. It was found that electric current produces a magnetic field and that a moving magnetic field produces electricity in a wire. This led to many inventions such as the battery (1800), generator (1831), electric motor(1831), telegraph (1837), and telephone (1876), plus many other intriguing inventions.

In 1879, Thomas Edison invented a more efficient lightbulb, similar to those in use today.

In 1882, he placed into operation the historic Pearl Street steam–electric plant and the first direct current (DC) distribution system in New York City, powering over 10,000 electric lightbulbs. By the late 1880s,

Power demand for electric motors required 24-hour service and dramatically raised electricity demand for transportation and other industry needs. By the end of the 1880s, small, centralized areas of electrical power distribution were spread across U.S. Cities. Each distribution center was limited to a service range of a few blocks because of the inefficiencies of transmitting Direct current. Voltage could not be increased or decreased using direct current systems, and a way to to transport power longer distances was needed.

To solve the problem of transporting electrical power over long distances, George Westinghouse developed a device called the “transformer”.

The transformer allowed electrical energy to be transported over long distances efficiently. This made it possible to supply electric power to homes and businesses located far from the electric generating plants. The application of transformers required the distribution system to be of the alternatingcurrent (AC) type as opposed to direct current (DC) type.

Since the early 1900s alternating current power systems began appearing throughout the United States. These power systems became interconnected to form what we know today as the three major power grids in the United States and Canada. The remainder of this chapter discusses the fundamental terms used in today’s electric power systems based on this history.
Do you feel confused confused about this lesson? Leave your question now in a comment.

Introduction to Hydro Power Plant

Introduction to Hydro Power Plant

A hydro power plant has an advantage in that it does not need fuels for its operation as compared with oil or thermal power plants. However, there are no differences between both types of plants in that appropriate operation and maintenance (O&M) are essential for their long-term operation. They can be operated for long periods if its facilities are properly operated and maintained. We should effectively utilize hydro power because aside from being an indigenous energy resource, it is also renewable.

We have to operate and maintain micro-hydro power plants with strict compliance to the operation and maintenance manuals. In general, operators of micro-hydro power plants should understand the following:

（１）Operators must efficiently conduct operation and maintenance of a plant complying with the work plans, rules and regulations.

（２）Operators must familiarize themselves with all the plant components and their respective performance or corrective and preventive functions. Furthermore, they must also be aware of measures against various accidents for prompt recovery.

（３）Operators must always check conditions of facilities and equipment. When they find some troubles or accidents, they must inform a person in charge and try to remedy the situation.

（４）Operators must try to prevent any accidents. For this purpose, they should repair or improve facilities preventively as necessary. Operation and maintenance manuals should basically be prepared for each plant

individually before the beginning of operation. The following are general manuals of

operation and maintenance for micro-hydro power plants.

Energy in Afghanistan and Afghanistan Power System Structure

 Energy in Afghanistan is primarily provided by hydro-power. According to the World Bank, approximately 84.1% of Afghanistan's population has access to electricity. Some rural areas, however, may not get 24-hour electricity but this will change once the major CASA-1000 project is completed in 2020.

According to Da Afghanistan Breshna Sherkat (DABS), Afghanistan generates around 300 megawatts (MW) of electricity mainly from hydro power followed by fossil fuel and solar. About 1,000 MW more is imported from neighboring Uzbekistan, Tajikistan, Iran and Turkmenistan.

Due to the large influx of expats from neighboring Pakistan and Iran, Afghanistan may require as much as 7,000 MW of electricity in the coming years.The Afghan National Development Strategy has identified alternative energy, such as wind and solar energy, as a high value power source to develop.

As a result, a number of solar and wind farms have been established, with more currently under development.

Frequency Control Of a Power System

  Frequency Control Of a Power System

How can the system frequency of a larger power system be adjusted without affecting the power sharing among the system generators?

It can’t unless each generator has room to move up and down in its allowed power output band. The power output band is defined as its maximum capacity minus its minimum capacity. Each generator has a maximum power output based on the unit size and a minimum power output based on both economics and engineering.

The frequency is determined by the ratio of load to generation. If there is too much generation then the frequency will rise. If there is too little generation then the frequency will drop. Assuming the load is fixed, the generation output has to be changed to adjust the frequency. If the balance of generation or the share of total output is to remain the same, then each generator has to be able to move up or down in its power output band to adjust the system frequency. Now this will never happen due to economics.

Each generator has a cost curve which dictates the price at each output range the generator will bid at. In the electric market the system will use the cost curves to find the most economical dispatch. This means some units with a lower price will be 100% committed to their maximum output while other more expensive units may be committed at their lowest output or below maximum.

The cost is dictated by several factors such as startup costs, fuel costs, and operations and maintenance (O&M) costs among others. At the Pmin - minimum power output the cost will be comprised of a startup cost plus fuel costs etc... As the units output rises, the startup cost stays fixed but the fuel and O&M costs rise.

The system frequency will be maintained by bringing generators online and offline in an economical order. As load rises the higher costs units will be brought online as all the lower units are already committed and generating.