Posts Tagged ‘rectifier’
July 7th, 2009 | 
Author: Wikipedia suggests that the inverter tag found on some air conditioners signifies the ability of the unit to continuously regulate its thermal power flow by altering the speed of the compressor in response to cooling demand. The name like Aircon in New Zealand makes sure that every one could experience the pleasing impact of the tag Mitsubishi Electric Invertors or Toshiba invertors or carrier inverters.
If we believe upon experts’ opinion then we find that inverter tag in air conditioners uses a variable-frequency drive to control the speed of the motor and thus the compressor. Experts further states that the variable-frequency drive uses a rectifier. This rectifier’s prime duty is to convert the incoming AC current to DC. After conversion of current, pulse-width modulation of the DC current within an inverter produces AC current of desired frequency.
In the beginning, there were several drawbacks with inverters. But now, numerous high-end inverters are available in the market. These are globally known for energy efficiency and reducing electricity bill. The grand success of inverter principle encouraged manufacturers and they are applying it into wide range of household appliances including microwave ovens, washing machines, and so on.
Experts suggest to consumer to check the inverter rating while you purchase. There are three types of inverter rating. At first, we can take the name ‘continuous rating’. This rating checks the capacity of inverter. It checks how long inverter can run without overheating and shutting down. If appliances are only to be used occasionally then half hour rating may well suffice. Sometimes, high surge is required when we start the appliances and then we need considerably less power. For these sorts of situation, we can use inverter based upon surge rating.
Apart from rating system, we should also have brief idea about types of inverters. Normally, we have two types of inverter in the market: modified sine wave (aka modified square wave) and true sine wave. If devices sense that either voltage peaks or zero crossings could have problems when running from modified sine wave then these should be run from true sine wave inverters.
Aircon Provide full information and Solutions of Mitsubishi Electric Air Conditioners, Mitsubishi Electric Invertors, Carrier Air Conditioner, Swimming Pool Heatpumps in Manukau City New Zealand.
Article Source: Inverters are truly awesome for reducing your electricity bill
After you study your text books it is important to test your newly acquired knowledge and see just how well you have absorbed the material. Practice exams….
* Reinforces what you learnt – fill in the gaps of what you missed
* Gets you used to answering questions to build confidence and familiarity
Here are 10 Multiple choice exams questions for you to practice on:
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Question 1# – Which program do we use to edit and configure programs that launch at startup?
A. Msconfig.exe
B. Regedit.exe / regedt32.exe
C. Cmd
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Question 2# – Which of the following components will hold a charge even through power has been removed?
A. Transistor
B. Capacitor
C. rectifier
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Question 3# – Your client’s computer refuses to connect to the network. You observe the NIC light is not ON and then use a different cable. What should you do next?
A. Attempt to log in to the server after again observing the NIC light status
B. Replace NIC
C. Replace NIC driver
D. Consider it fixed
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Question 4# – you have installed an external device but your computer isn’t recognizing it. What are some questions you should ask yourself and/or do?
A. Is the device plug and play?
B. Turn the computer and device off. Wait and then turn the device on. And then the computer.
C. Is the device connected properly to the computer?
D. All the above
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Question 5# – You have been working on your computer the day installing a new hard drive and now notice the light on the floppy drive is lit when you powered on the computer. What is the problem?
A. The hard drive is installed the wrong way
B. The data cable of the floppy drive is installed backwards
C. Only one end of the floppy drive cable has been installed
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Question 6# – what are hot swappable devices?
A. Devices that can be added or removed while the computer is on and working
B. Devices that can be added without the need of drivers
C. Devices that have a USB connection there you can hot swap them on the same USB port on the computer
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Question 7# – what are the benefits of cleaning the computer on the inside? Choose all that apply
A. provides better system cooling
B. reduces the risk of components failure
C. increases data transfer speed
D. all the above
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Question 8# – You are about to install a second IDE hard drive in a PC that has only one IDE adapter. Your first hard drive will still be the boot drive. How should the second drive be configured?
A. as a master
B. as a secondary
C. as a slave
D. as a primary
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Question 9# – TSR stands for?
A. Terminate and Stay Resident
B. Transmit-Send-Receive
C. Test and Set RAM
D. Terminate and Save Register contents
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Question 10# – You have just printed a document on a laser printer but its come out with a wavy image. What is the most likely cause of this?
A. Defective laser scanner
B. Defective rollers
C. Defective corona
D. Defective toner cartridge
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ANSWERS
Question 1 – Correct Answers: A
Question 2 – Correct Answers: B
Question 3 – Correct Answers: A
Question 4 – Correct Answers: D
Question 5 – Correct Answers: B
Question 6 – Correct Answers: A
Question 7 – Correct Answers: A,B
Question 8 – Correct Answers: C
Question 9 – Correct Answers: A
Question 10 – Correct Answers: A
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By Georgie Stath – Certification Help is a beginners guide to getting certified. Also find 8 Accelerated Learning Techniques that will see you getting certified faster.
Article Source: 10 Practice Questions Comptia Exams A+ IT Technician