BEE-CHAPTER 5_Electrical Wiring and Installation.pptx

[9/16, 2:35 PM] Meta AI: Here's a potential description for a PPT on bees and food waste reduction:

*Title:* "The Buzz on Food Waste: How Bees Can Help"

*Objective:* To highlight the importance of bees in food production and the impact of food waste on bee populations, while providing solutions for reducing food waste and supporting bee conservation.

*Key Points:*

1. *The Role of Bees:* Bees are crucial pollinators, contributing to global food security and ecosystem health.
2. *Food Waste Impact:* Food waste affects bee populations by reducing the availability of nectar and pollen-rich flowers.
3. *Solutions:* Strategies for reducing food waste and supporting bee conservation, such as:
- Planting bee-friendly flowers and herbs
- Reducing pesticide use
- Supporting local beekeepers and sustainable agriculture
- Composting food waste to create nutrient-rich soil
4. *Bee-Friendly Practices:* Tips for individuals and communities to support bee health, such as:
- Creating bee-friendly gardens
- Avoiding single-use plastics
- Supporting
[9/16, 2:35 PM] Meta AI: Here's a potential description for a PPT on bees and food waste reduction:

*Title:* "The Buzz on Food Waste: How Bees Can Help"

*Objective:* To highlight the importance of bees in food production and the impact of food waste on bee populations, while providing solutions for reducing food waste and supporting bee conservation.

*Key Points:*

1. *The Role of Bees:* Bees are crucial pollinators, contributing to global food security and ecosystem health.
2. *Food Waste Impact:* Food waste affects bee populations by reducing the availability of nectar and pollen-rich flowers.
3. *Solutions:* Strategies for reducing food waste and supporting bee conservation, such as:
- Planting bee-friendly flowers and herbs
- Reducing pesticide use
- Supporting local beekeepers and sustainable agriculture
- Composting food waste to create nutrient-rich soil
4. *Bee-Friendly Practices:* Tips for individuals and communities to support bee health, such as:
- Creating bee-friendly gardens
- Avoiding single-use plastics
- Supporting pollinator conservation initiatives
5. *Call to Action:* Encourage individuals, communities, and organizations to take action to reduce food waste and support bee conservation.

*Visuals:* Incorporate images of bees, flowers, and sustainable practices to illustrate the importance of bees and the impact of food waste.

*Tone:* Informative, engaging, and inspiring.

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1. Chapter – 8 Protection and Utilization of Electrical Power 1

2. High Rupturing Capacity (HRC) Cartridge Fuse capsule Rewirable Fuse FUSE

3. Important Terms in Fuses Current rating of fuse element:  It is the current which the fuse element can normally carry without overheating or It depends upon the temperature rise of the contacts of the fuse holder, fuse material and the surroundings of the Fuses. Fusing current:  It is the minimum current at which the fuse element melts and thus disconnects the circuit protected by it. Obviously, its value will be more than the current rating of the fuse element. For a round wire, the approximate relationship between fusing current I and diameter d of the wire is I = kd 3/2 where k is a constant, called the  fuse constant . Fusing factor:  It is the ratio of minimum fusing current to the current rating of the fuse element Steps: Melting of silver elements (pre-arcing) Vaporization of the elements (Arcing) Fusion of silver vapor and filling powder Arc extinction

4. FUSE   The fuse is a protective device, which is used to protect circuits from over current, overload and make sure the protection of the circuit. Fuse consists of a low resistance metallic wire enclosed in a non-combustible material. Whenever a short circuit, over current or mismatched load connection occurs, then the thin wire inside the fuse melts because of the heat generated by the heavy current flowing through it. Therefore, it disconnects the power supply from the connected system. In normal operation of the circuit, fuse wire is just a very low resistance component and does not affect the normal operation of the system connected to the power supply.   TYPES OF FUSES According to voltage level, fuses are classified in two category. (1) Low voltage fuse (2) High Voltage Fuse. The low voltage fuses are further classified as Semi Enclosed or Rewirable Type Totally enclosed or Cartridge Type.

5. Semi Enclosed or Rewirable Typ e Renewable fuse consists of a base and a separate fuse element carrier made of porcelain . The base consists of two terminals one for incoming supply and the other for the outgoing supply. Similarly fuse carrier also contains two terminals between which fuse element is connected. The fuse base and the carrier are designed such that each terminals of base coincides with a terminal of the fuse element. The circuit will be closed only if the fuse carrier is inserted into the base and the fuse element is continuous. The main metals or alloys used in making fuse wire include lead, tinned copper, aluminum or tin lead alloy. Once the fuse is blown out, it can be reused by replacing the fuse element with a new one. ADVANTAGE: • cheap DISADVANTAGE: disadvantages are • chances of incorrect replacement • subject to deterioration with time • higher fusing factor (up to 2) than cartridge fuses (1.25 to 1.6) • characteristic unreliable making discrimination difficult

6.   (2) HRC fuse HRC Fuse consists of highly heat resistant material (such as ceramic) body having metal-end caps, which is welded by silver current carrying element. The fuse body internal space is completely packed with a filling powder. The material, which has filled the insider space, may be plaster of Paris, quartz, chalk, marble, dust and cooling mediums etc. That’s why it carries normal current without overheating. When a fault occurs, the current increases and the fuse element melts. The heat being produced vaporizes the silver melted element. Chemical reaction taking place between silver vapor and filling powder results in high resistance substance, which helps in quenching the arc in fuse. Advantages of HRC Fuse: It clears high as well as low fault currents. Do not deteriorate with age. Having high-speed operation. Provides reliable discrimination. Require no maintenance. Permit consistent performance Fusing operation is fast without Noise and Smoke Disadvantages of H.R.C Fuse: After each operation, they have to be replaced. Heat being produced by the arc may affect the associated switches. Preferred ratings of HRC fuses are 2, 4, 6, 10, 16, 25, 30, 50, 63, 80, 100, 125, 160, 200, 250, 320, 400, 500, 630,800, 1000 and 1,250 amperes.

7. Miniature circuit breaker (MCB) MCB s or  Miniature Circuit Breakers  are electromechanical devices which protect an electrical circuit from an overcurrent. The overcurrent, in an electrical circuit, may result from short circuit, overload or faulty design. An MCB is a better alternative to a Fuse since it does not require replacement once an overload is detected. Unlike fuse, an MCB can be easily reset and thus offers improved operational safety and greater convenience without incurring large operating cost. There are two arrangement of  operation of miniature circuit breaker . One due to thermal effect of over current and other due to electromagnetic effect of over current. The thermal  operation of miniature circuit breaker  is achieved with a bimetallic strip whenever continuous over current flows through MCB, the bimetallic strip is heated and deflects by bending. This deflection of bimetallic strip releases mechanical latch. As this mechanical latch is attached with operating mechanism, it causes to open the miniature circuit breaker contacts. But during short circuit condition, sudden rising of current, causes electromechanical displacement of plunger associated with tripping coil or solenoid of MCB. The plunger strikes the trip lever causing immediate release of latch mechanism consequently open the  circuit breaker  contacts.

8. Construction of MCB Actuator lever: Used to manually trip and reset the circuit breaker. Also indicates the status of the circuit breaker (On or Off/tripped). Most breakers are designed so they can still trip even if the lever is held or locked in the on position. This is sometimes referred to as "free trip" or "positive trip" operation. Actuator mechanism : Forces the contacts together or apart. Contacts: Allow current to flow when touching and break the flow of current when moved apart. Terminals Bimetallic strip Calibration screw: Allows the manufacturer to precisely adjust the trip current of the device after assembly. Solenoid Arc divider/Extinguisher

9. MCCB

10. ELCB An  Earth Leakage Circuit Breaker  used to detect a current flowing in the safety “ground” or “earth” wire. If there is no problem at anyplace at any circuit, powering single-phase alternating power to a unit such as an electrical appliance, appliance or other electrical apparatus, the current flowing to the unit at any instant in the “live” wire should exactly match the current flowing from the unit in the neutral wire. Similarly, there should be no current flowing in the unit’s safety or “earth” wire. It is an elementary fact of electrical engineering design that all current flowing to an electrical machine, machine or other gear from the power generation station via its supply circuit’s “live” wire should only return to the power station via that same circuit’s “neutral” wire.  So, as a result of that basic fact, if any current is going in the ground wire, it must be caused by a wrong condition and the supply of current to the circuit needs to be stopped urgently. Many years ago, before today’s electronic RCDs or GFCIs were  been designed, much simpler electro-mechanical relays called Earth Leakage Circuit Breakers (ELCBs) were invented so that, if any such ground current exceeding just a few milliamps were detected, they would “trip” – meaning “operate” – to break the current supply to the circuits for which they were installed to shield. If ELCB  did not check for any difference in current flowing in the live and neutral wires, which is another indication of a very serious fault condition – even if no current can be detected flowing in the ground wire – because the “missing current” may actually be flowing to ground via someone’s body!

11. To understand the working of ELCB refer following figure.

12. Disadvantages of HRC Fuse : 1. After each operation, it must be replaced. 2. It cannot be interlocked with other devices. 3. Its contacts can be affected by heat produced during the operation of fuse. There are also known as High Rupturing Capacity (HRC) fuse. These types of fuses are used for industrial as well as distribution purpose. The HRC type fuses are designed to protect the equipments against very high current and In this type of fuse, the arc produced during the operation of the fuse element is extinguished by quartz sand powder. Advantages of HRC Fuse 1. It can interrupt very high current. 2. Its operation is very fast. 3. Inverse time – current characteristics. 4. Low cost compared to other protective device. 5. Required no maintainace. 6. Their operating characteristics are accurately known. Advantages : 1. Simplest form of protective device. 2. Automatic operation 3. Very low cost. 4. Required no maintainace. 5. Minimum value of current can be interrupted by fuse. 6. Inverse time – current characteristics. Disadvantages : 1. After fuse operation, fuse or fuse element required to be replaced. 2. Replacement process is time consuming. 3. Required characteristics cannot be obtainable. The current capacity of the fuse wire should not exceed 5 A when used for lighting load and not exceed 10 A when used for power load. All the power devices should have different circuit. Total load in the circuit should not exceed 1000 watt and the number of points in each circuit should not exceeds 10. The general rules for any domestic wiring are described below; 1. Fuse 2. Miniature Circuit Breaker (MCB) 3. Earth Leakage Circuit Breaker (ELCB) The three phase system should be indicated by Red (R phase), Yellow (Y phase), Blue (B phase) and Black (neutral). th Main Function : Their main function of the protective devices is to detect the faulty condition and disconnect the faulty parts or circuit from the system. Construction of Fuse Generally, the three protective devices are used in the household applications as listed below; 1. Fuse Element Main Function : Function : When current flowing through the fuse element exceeds its predetermined value then the fuse wire melts down and it interrupts the current flowing through the circuit. Hence, it protects the circuit from the excessive current. 2. Fuse Body Types of Fuse The different types of fuses are given below; 1. Open type fuse 2. Rewirable type or semi-enclosed types fuse 3. Cartridge type fuse 4. HRC fuse  Fluorescent Lamp or Tube  Fluorescent Lamp Construction 4. It consist two electrodes P and Q, made in spiral form, each made from tungsten material. 3. The small amount of mercury and argon gas is filled in the tube. 1. It is a one type of glass tube. 2. This tube is coated by fluorescent powder (phosphor) internally. 5. These electrodes are coated by electron emitting material. Chock 1. The chock is connected in series with the tube light. 2. Its main function is to induce the high voltage to produce the flow of electrons in the tube and to start the tube light. 3. It also works as ballast.   Starter 1. The starter is connected with the tube light. 2. It consist a bimetallic switch which is normally open and capacitor C. 3. The bi-metallic switch is made from two different materials having different temperature co-efficient. 4. Its main function is to start the tube light. 5. The capacitor is used to suppress the radio interference produced due to arc.  General Rules for Wiring  All the switches should be connected on the live wires. Three pin plugs should be used in residential application. All the neutral wires should be linked. All the switch boards should be fixed at height of 1.5 meter from ground level. All the fans should be fixed at height of 2.5 meter from ground level.  Protective Devices   Fuse  3. End Caps 5. Arc Quenching Medium  HRC Fuse  Fuse Body End Cap End Cap Terminals Terminals Fuse Element Vacuum or Quartz Sand powder 4. Terminals Capacitor Bi-Metallic Strip AC CHOCK FLOURECENT LAMP P Q STARTER WORKING

13. Sr. No. MCB ELCB 1 Full Name : Miniature Circuit Breaker. Full Name : Earth Leakage Circuit Breaker. 2 For overload and short circuit protection. For earth leakage protection. 3 It operates when the current flowing through it exceeds its rated value. It operates when the current flowing through the phase to earth. 4 Rating: Ampere. Rating : mA . The strip is mounted nearer to heating resistance which produce the heat when the current passing from the resistance.  Miniature Circuit Breaker (MCB)  Function : When current flowing through the MCB exceeds its rated value then the bimetallic strip will be bend which disconnect the faulty parts and it interrupts the current flowing through the circuit. Hence, it protects the circuit from the excessive current. Construction of MCB 1. The MCB consist a bi-metallic strip. The bi-metallic strip is made from two different materials having different temperature co-efficient. The spring is used in between the contacts and the bi-metallic strip.  Earth Leakage Circuit Breaker (ELCB)  The ELCB is a protective device. It protects the circuit when the leakage current flowing through the earth. It is always connected in series with earth wire. (In between outer frame of electrical machine and earth). In other words, it gives the protection against electric shock. The ELCB is widely used in the household applications to protect against earth leakage. Function : When the leakage current flowing through the ELCB, it will operates and its contacts placed in the main line circuit will be open. Hence, it protects against the earth leakage.  Difference between MCB and ELCB   Electrical Earthing  Function : The different function of the earthing is describe below; 1. To maintain proper function of the electrical system. 2. To provides the protection to the person against electric shock. 3. To protect the large building against lightning. 4. To maintain constant line voltage.  Necessity of Electrical Earthing  Machine is Not Earthed Machine is Earthed AC P N Electrical Machine Person Earth I I I b I b I b AC P N Electrical Machine Person Earth I I I e I e I e I I Heating Resistance Bi-metallic Strip To Load Spring

14.  Types of Earthing  The earthing can be done by connecting the outer frame of all electrical appliances/machines to the earth through the low resistance conductor. There are main two methods for earthing; 1. Pipe Earthing 2. Plate Earthing 15

15. Ground 2 mt 2 mt Coal Salt Coal Salt Salt Coal Salt Coal 12 mm Diameter 38 mm G.I. Pipe 15 cm 15 cm 19 mm G.I. Pipe 12.7 mm G.I. Pipe 60 cm Cement Concrete Cast Iron Cover Ground  Pipe Earthing 

16. Pipe earthing Pipe earthing is best form of earthing and it is cheap also in this system of earthing a GI pipe of 38 mm dia and 2meters length is embedded vertically in ground to work as earth electrode but the depth depend upon the soil conditions, there is no hard and fast rule for this. But the wire is embedded up to the wet soil. The earth wire are fastened to the top section of the pipe with nut and bolts. The pit area around the GI pipe filled with salt and coal mixture for improving the soil conditions and efficiency of the earthing system. It can take heavy leakage current for the same electrode size in comparison to plate earthing. The earth wire connection with GI pipes being above the ground level can be checked for carrying out continuity test as and when desired, while in plate earthing it is difficult. In summer season to have an effective earthing three or four bucket of water is put through the funnel for better continuity of earthing.

17. G.I. Plate 60 cm * 60 cm * 6.3mm Ground 3 mt 15 cm 90 cm  Plate Earthing  12.7 mm GI. Pipe 19 mm G. I. Pipe Tunnel 30 cm * 30 cm 60 cm Alternative Layer of Coke & Salt Cast Iron Cover Ground

18. Plate Earthing In this type of earthing plate either of copper or of G.I. is buried into the ground at a depth of not less than 3 meter from the ground level. The earth plate is embedded in alternative layer of coke and salts for a minimum thickness of about 15cm. The earth wire(copper wire for copper plate earthing and G.I. wire for G.I. plate earthing) is securely bolted to an earth plate with the help of bolt nut and washer made of copper, in case of copper plate earthing and of G.I. in case of G.I. plate earthing.

19.  What is Electric Shock ?  Definition : The nervousness of the human body due to sudden passage of electric current through the body is known as electric shock. The electric shock depends on the following factors; 1. Magnitude of current flowing through the body. 2. Time for which the current flowing through the body. 3. Frequency of the current flowing through the body. 4. Physical condition of body of the person. There are three main types of electrical injuries; 1. Electrocution (death due to electrical shock) 2. Electrical shock 3. Burns  Power Factor  1 st Definition : The cosine of the phase angle between the supply voltage applied to the circuit and the current flowing through the circuit is known as the power factor. It is denoted by Cos ϕ. 2 nd Definition : It is also defined as the ratio of resistance to the impedance. 3 rd Definition : It is also defined as the ratio of active power to the apparent power.  Disadvantages of Low Power Factor  Large Cross Sectional Area of Conductor Higher I 2 R Losses Lower Efficiency Less Voltage at Terminal Poor Voltage Regulation Reduction in KW Capacity  Causes for Low Power Factor  Induction Motor Agricultural Pump Set Arc Furnace and Induction Furnace Arc Lamps and Electric Discharge Lamps Arc Welding Over Rating of Equipments Increase in System Voltage  Advantages of the Power Factor Improvement  Small Cross Section Area of Conductor Increased KW Capacity Reduction in I 2 R Losses Higher Efficiency Better Voltage Regulation Low Running Cost  Methods to Improve Power Factor  Using high power factor motors Using phase advancer with induction motor Using capacitor booster Using static capacitor Using Synchronous condenser 20

20. ELECTRICITY BILL CALCULATION FOR HOUSE LOAD SR.NO TYPE OF LOAD NOS. WATT(W) TOTAL WATT(W) TIME PER DAY(HOURS) PER DAY UTILIZATION (W*h) 1 FAN 3 60 180 7 1260 2 LIGHT-LED 5 12 60 5 300 3 LIGHT-TUBE LIGHT 1 60 60 4 240 4 GEYSER 1 3000 3000 1 3000   PER DAY UTILIZATION (W*h) 4800   (CURRENT MONTH,MONTHLY,BIMONTHLY,LEAP YER)TOTAL DAYS 60   TOTAL UTILIZATION(W*h) 288000   NO. OF UNITS=kWH=W*h/1000 288   RATE OF UNIT(Rs.) 8.5   TOTAL BILL AMOUNT(Rs.) 2448