Domestic wiring ppt

It is simple and easy to Understand

1. Shakeel Ahmed Saad Affandi Tahir Tanoli Mustafa Ahmed Group Members

2. Electrical power is transferred from generating stations to consumers at different voltage levels. Electrical power can be considered just like gas or water and same rule applies to its distribution i.e. proper pipeline and associated valves/switches. Introduction

3. DOMESTIC WIRING Domestic wiring may be defined as Wiring done in domestic houses, for providing electrical power for lighting, fans and domestic appliances with all the safety precautions followed is called domestic wiring. Domestic wiring

4. Durability : Type of wiring selected should conform to standard specifications, so that it is durable i.e. without being affected by weather conditions, fumes etc. Electrical Safety: The wiring must provide safety against leakage, shock and fire hazards for the operating personnel. Factors Affecting The Choice Of Wiring

5. Appearance: Electrical wiring should give an aesthetic appeal to the interiors. Cost: It should not be prohibitively expensive i.e. the system chosen should depend upon the type of building and the purpose for which it is used, keeping economy in view. Factors Affecting The Choice Of Wiring

6. Accessibility: The switches and plug points provided should be accessible and there must be provision for further extension of the wiring system, if necessary. Maintenance Cost: The maintenance cost should be minimum. Mechanical Safety: The wiring must be protected against any mechanical damage. Factors Affecting The Choice Of Wiring

7. Parallel Wiring Switch Wiring Series Wiring Types of wiring

8. Parallel Wiring The wiring for most homes is parallel, meaning several devices are powered on a single circuit. Both the hot and neutral wires run through the various housing boxes along the route and branch off to individual fixtures and receptacles. Types of wiring

9. switch wiring Switches, which are installed on hot wires, allow or disallow the flow of current to a light or other device. A knife-blade switch (shown at right) illustrates the position of the switch when it completes a circuit, allowing electricity to power a device. The illustration below it shows the position of the switch when it interrupts the flow of current from the hot bus bar, disallowing the flow of electricity. Types of wiring

10. Series Wiring This type of wiring is rarely used because it operates the same as old-style Christmas lights—when one light burned out, none would illuminate. Series wiring routes the hot wire through several devices and then joins the neutral wire, which leads back to the source. Types of wiring

11. Basic home wiring circuits

12. The electricity from the mains is supplied to the houses using a three-core wiring. They are The Live wire The neutral wire and The earth wire DOMESTIC ELECTRIC CIRCUITS

13. Live Wire: It is at a high potential of 220 volts. The live wire has red insulation Neutral wire: It is at the ground potential of zero volt. The neutral wire has black insulation covering.From the electric pole situated in our street, two insulated wires L and N come to our house. In India, the potential difference between the two wire is 220V. The Earth wire : It is a safety measure and does not affect the supply in any way. The green earth wire is connected to a metal plate deep in the earth. DOMESTIC ELECTRIC CIRCUITS

14. Earthing of an electrical appliance means connecting the metallic body of the powered appliance to the earth through the earth wire. It is a safety measure which ensures any leakage of current to the metallic body of the appliance. This is done by keeping the potential of metallic body equal to that of the earth (zero volt) and the user may not get a severe electric shock by means of a metal wire called “earth wire”. DOMESTIC ELECTRIC CIRCUITS

15. If due to defective or damage wiring, the live and neutral wires come in direct contact, the resistance of the circuit becomes almost zero and an extremely large current flows through the circuit. This is called short circuiting. Appliances can be protected from short circuiting by using an electric fuse in live wire SHORT CIRCUIT

16. If the current drawn from the mains exceeds the safety limit (5 A for domestic line and 15 A for power line), then this is known as overloading. A circuit can be protected from overloading by using an electric fuse. OVERLOADING

17. It is a safety device to protect an electric circuit from overloading or short circuiting. It is a piece of wire of a material of low melting point which is connected to the live wire in the circuit. A fuse wire is connected in series in the electric circuits. When an excessive current flows, the fuse melts and the circuit is broken. The fuse wire must have proper thickness which depends on the maximum current which the household wiring can safely carry. ELECTRIC FUSE

18. The two main organs of the human body where the magnetic field produced is quite significant are the heart and the brain. The magnetism produced inside the human body (by the flow of ionic currents) forms the basis of a technique called Magnetic Resonance Imaging (MRI) used to obtain images (or pictures) of the internal parts of our body. MAGNETISM IN HUMAN BEINGS