Contactors are used to control electric motors, lighting, heating, capacitor banks, thermal evaporators, and other electrical loads. Utilization categories for contactors are defined by IEC standards and indicate the type of electrical load and duty cycle of the loads to ease selection of contactors.
Symbol (According to standard IEC 60617: S00218):
Construction:
A contactor has three parts. The contacts are the current carrying part of the contactor. This includes power contacts, auxiliary contacts, and contact springs. The electromagnet (or coil) provides the driving force to close the contacts. The enclosure is a frame housing the contact and the electromagnet.
Operating principle:
When current passes through the electromagnet a
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TASK 2
Understanding of Distribution Factors
1- Load Factor:
The load factor is defined as the average load divided by the peak load in a specified time period. It can be derived from the load profile of the specific device or system of devices. It is given by the following formulae:
Diversity Factor:
The diversity factor can be defined as the sum of the individual maximum demand to the maximum demand on the source. Proper understanding of diversity factor is vital in designing of switchgears and in the selection of transformers, feeders etc. The simultaneous function of all installed loads of a given installation never occurs in practice, i.e. there is always some degree of diversity and this fact is taken into account for estimating purposes by the use of a factor (ks).
This factor is defined in IEC60050 - International Electrotechnical Vocabulary, as
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The motor load factor is then 12/15 = 80%. The motor above may only be used for eight hours a day, 50 weeks a year. The hours of function would then be 2000 hours, and the motor use factor for a base of 8760 hours per year would be 2000/8760 = 22.83%. With a base of 2000 hours per year, the motor use factor would be 100%.
2- Maximum Demand:
Maximum Demand is the power consumed over a predetermined period of time, which is usually between 8– 30 minutes. The most common period of time, in the majority of countries, is 15 minutes.
Maximum Demand can be measured with a device commonly known as Maximum Demand Indicator (MDI).
Earthing and Types Of Earthing:
In electricity supply systems, an earthing system or grounding system is circuitry which connects parts of the electric circuit with the ground, thus defining the electric potential of the conductors relative to the Earth's conductive surface. The selection of earthing system has a direct impact on the safety and the electromagnetic compatibility of the source. There are two types of earths namely Protective Earth (PE) and Functional
8. If a coal-burning electrical generating plant burns 2 tons of coal to generate 6000 kWh of electricity, calculate the efficiency of the plant as the ratio of electricity output to fuel energy input (refer to Table 3.4).
The new lift has an economic life of 20 years and we would like to make 14% on our investment. The NPV factor of 14% at 20 years is 6.6231. By multiplying our net yearly income or our annuity of $500,000 times the NPV factor of 6.6231 we will have a NPV of $3,311,550.
The title, Where the Telemetries End, plays on the word “telemetry.” Again, telemetry is the collection of sensory information that is later transmitted by radio waves to another location. Every day we experience events that are sometimes positive and enriching, and others that leave us with emotional scars. Burned into us, is every vivid detail of these events, due to their emotional impact. Think of something that happened to you in the past, something that caused you sadness to the point of tears. I bet you can recall every bit of sensory information that you experienced during that time. Sometimes this sensory information, such as pictures of loved ones or the smell of old clothes, triggers our recollection of such events. If they are especially painful to us, we try to repress these feelings; however, out of thin air they come back to haunt us again and again. This is behavior comparable radio waves, which appear out of thin air and express information. Telemetry, if you will. And so this leaves both the reader and main persona asking, “Where the telemetries end,” and do they
For the beginners who want to know how to prepare your contacts, how to insert your contacts, and how to remove your contacts. To begin with, you will need to use the following: a sink, hand soap, paper towels. Before you do anything with your eyes, you want to make sure that your hands are clean and free of any bacteria.
The risk management plan is for Flayton Electronics following their breach in security of their customer’s information. The document provides an explanation and description of the risk management process undertaken throughout the life cycle of this project. The project manger will be responsible for reviewing and maintaining the Project Risk Management Plan. The manager will ensure that all the risk process factors are appropriate to deal with the risks highlighted in the project.
...rn, M., Ramroth, L., & Lovins, A. B. (2008). Transformational trucks: determining the energy efficiency limits of a class-8 tractor-trailer. Rocky Mountain Institute, Snowmass, CO.
· B-phase transformer (EMTU-TT01) · Feedback electronic wattmeter · Multi-range moving-iron ammeter · Instrument voltage transformer THEORY AND INTRODUCTION ----------------------- Transformers are used all over the world to step-up and step-down electricity. The transformer is one of the most commonly used electrical devices. The reason the transformer is so popular is because they range in size from 240V to well over 240kV, stepping -up and stepping-down electricity all over the world.
Contact from an un-identified being can be unnerving, however Dr. Ellie Arroway has spent years looking for other life form outside of Earth and when she first heard a possible message coming from the Vega star system she was ecstatic. After spending close to 10 years listening for radio signals Dr. Ellie had finally heard a message from a life from light years away. As news of the signal spread through the world, outbreaks of both panic and amusement occurred by everyone who heard. In the message was an encrypted video feed that included design plans for a wormhole generator. One trillion dollars later it was built and after a hard thought out vote, Dr. Ellie was nominated to be put in the machine. After two attempts she makes her two-hour journey through time toward the Vega galaxy. She arrives and sees the “alien,” who explains to her why they contacted earth. The “aliens” return Dr. Ellie and she comes back to earth with no evidence of the encounter. This causes a conflict with the people on whether to believe in her encounter with aliens.
Located in Source C, the chart demonstrates how many watts of electricity are used per electronic device. It states, “Our total daily energy consumption is 5,025 watt-hours, or about 5 kilowatt-hours.” Wow. Just take a second and realize how much energy we truly consume per day. With the use of fossil fuels such as coal, oil, and natural gas it allows for non-renewable energy to be burned to produce energy.
Electricity and electrical components are a major part of our lives today. Our lives pretty much come to a halt if there is a power outage or if our electrical devices stop working, sometimes we even start panicking because we are so dependent on these components that we cannot afford to lose them and their importance and use only increases as time passes. We all use these electrical devices and also electricity itself but most of us do not think about the math and physics that works behind all of these things.
The sound waves from the caller's voice cause the plastic disk to vibrate, changing the distance between the disks, thus changing the intensity of the electric field. These variations are translated into an electric current which travels across the telephone lines. The receiver of a telephone is composed of a flat ring of magnetic material. Underneath this magnetic ring is a coil of wire where the electric current flows. Here, the current and magnetic field from the magnet cause a diaphragm between the two to vibrate, and replicate the sounds that are transformed into electricity.
An easy way to calculate the load factor is to find out the total floor area of the building, by subtracting the shared square footage, from your answer to obtaining the usable square
There are sometime thing that even you can’t accomplish be yourself, If you know you can't do something ask someone else for help when working as an electrician. Safety is the most important thing that is needed when being an electrician and working with electricity. When asking for help your co-workers will help you, because you help each thought out the whole project. That is friendship that is alway needed in a job.Safety is the first priority that is needed to be followed without anyone telling you. Don’t joke around when you are working near electricity. You should be serious in willing to help when you are needed or when you need help.
Electrical engineering deals with electricity, electro-magnetism and electronics. It also covers power, control systems, telecommunications and signal processing. These engineers are usually concerned with large-scale electrical systems such as motor control and power transmission, as well as utilizing electricity to transmit energy. Electrical engineers may work on a diverse range of technologies, from the design of household appliances, lighting
In power stations electricians need to use a variety of device to ensure that they are doing the job correctly. The four essential things an electrician needs to consider is earth wire, double insulation, fuse box and a residual circuit breaker. These four things are essential because they help to increase the health and safety of workers.