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Keep Customers Happy With Internet Answering Services

Keeping customers happy is an important goal for businesses in any market. One of the ways this is done by providing excellent support through efficient, timely and effective customer service. An excellent customer service operation is one of the hallmarks of a good company. Customers tend to judge you to a large extent on the strength of the service that they receive.


Pwm Based Speed Control of Dc Motor Drive

Introduction When the switch is closed, the motor sees 12 Volts, and when it is open it sees 0 Volts. If the switch is open for the same amount of time as it is closed, the motor will see an average of 6 Volts, and will run more slowly accordingly. As the amount of time that the voltage is on increases compared with the amount of time that it is off, the average speed of the motor increases. This on-off switching is performed by power MOSFETs. A MOSFET is a device that can turn very large currents on and off under the control of a low signal level voltage. The time that it takes a motor to speed up and slow down under switching conditions is dependant on the inertia of the rotor , and how much friction and load torque there is. The graph below shows the speed of a motor that is being turned on and off fairly slowly: We can see that the average speed is around 150, although it varies quite a bit. If the supply voltage is switched fast enough, it wonò€™t have time to change speed much, and the speed will be quite steady. This is the principle of switch mode speed control. Thus the speed is set by PWM. Inductors Before we go on to discuss the circuits, we must first learn something about the action of inductive loads, and inductors. Inductors do not allow the current flowing through them to change instantly (in the same way capacitors do not allow the voltage across them to change instantly). The voltage dropped across an inductor carrying a current i is given by the equation Where di/dt is the rate of change of the current. If the current is suddenly changed by opening a switch, or turning a transistor off, the inductor will generate a very high voltage across it. For example, turning off 100 Amps in 1 microsecond through a 100 microHenry inductor generates 10kV! PWM frequency The frequency of the resulting PWM signal is dependant on the frequency of the ramp waveform. Frequencies between 20Hz and 18kHz may produce audible screaming from the speed controller and motors. Each switching on and off of the speed controller MOSFETs results in a little power loss. Therefore the greater the time spent switching compared with the static on and off times, the greater will be the resulting "switching loss" in the MOSFETs. The higher the switching frequency, the more stable is the current waveform in the motors. This waveform will be a spiky switching waveform at low frequencies, but at high frequencies the inductance of the motor will smooth this out to an average DC current level proportional to the PWM demand. This spikiness will cause greater power loss in the resistances of the wires, MOSFETs, and motor windings than a steady DC current waveform. It can be seen from the following two graphs. One shows the worst case on-off current waveform, the other the best case steady DC current waveform Both waveforms have the same average current. However, when we work out the power dissipation in the stray resistances in our motor and speed controller, for the DC case: and for the switching case, the average power is So in the switching waveform, twice as much power is lost in the stray resistances. In practice the current waveform will not be square wave like this, but it always remains true that there will be more power loss in a non-DC waveform. Choosing a frequency based on motor characteristics Then we can work out mathematically the minimum frequency to attain this goal. This section is a bit mathematical so you may wish to miss it out and just use the final equation. The following shows the equivalent circuit of the motor, and the current waveform as the PWM signal switches on and off. This shows the worst case, at 50:50 PWM ratio, and the current rise is shown for a stationary or stalled motor, which is also worst case. T is the switching period, which is the reciprocal of the switching frequency. Just taking the falling edge of the current waveform, this is given by the equation ? is the time constant of the circuit, which is L / R. So the current at time t = T/2 (i1) must be no less than P% lower than at t = 0 (i0). This means


Communication

Nokia 6280: Experience the Power of 3G Technology

Innovation is the buzz word in the world of mobile phones, as more and more sophisticated phones are hitting the mobile market every day. Making things more easier and convenient, the mobile phones are rapidly becoming our most reliable gadgets. Moreover, the advent of 3G technology has also brought many revolutionary changes in the way we communicate or we surf the Internet. Nokia, the world leader as a mobile manufacturer has always taken the initiative to bring all the latest features and technology at your fingertips in the most convenient way. Living up to the expectations, the Nokia introduced its another gizmo ò€“ the Nokia 6280, which is packed up with substantial features.

Nokia 8800 Sirocco Gold: Where Luxury Meets Exclusivity

If you believed in the age old dictum which said that all that glitters is not gold, then you will have to eat back your words when you will meet the latest presentation from the Nokia factory. It is called Nokia 8800 Sirocco Gold, which is all set to be the latest elaborate accessory for the elite class that comes with a bling factor. This exclusive gadget stands out from the crowd of similar looking handsets that look horribly alike. Sirocco Gold is a rarity that comes in the form of this ornamental mobile handset.

Nokia E63 Ultimate Messaging Mobile

Nokia E63 is a full-fledged dynamic smartphone, designed to portray a strong built character. The colors of the mobile and the frame speak out all about this device. It portrays a personality comparable to big boss image.

Nokia and Tata DOCOMO take Nokia Ovi Life Tools to Rural India

Nokia India has tied up with Tata DOCOMO to offer Nokia Ovi Life Tools to a larger base of consumers in rural and semi-urban India. Nokia Ovi Life Tools are groundbreaking services specifically created for the emerging markets to plug information gaps in the areas of agriculture, education and entertainment.

Norstar? Avaya? How do I buy a business phone system?

3 Simple Parts ð€“ Lines, Stations, and Voice mail

Online Conferencing ò€“ Providing Better Growth Opportunities to Organizations

The waves of web conferencing stroke the markets some time back. Due to the wide array of benefits offered by these services, it was widely accepted by a number of business organizations who had to communicate regularly with their clients and employees situated in different corners of the world.

Optimizing the Use of Your Prepaid Calling Card Credits

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PBX Phone Systems - An Affordable Solution for Small and Home Offices

To remain ahead in the competitive business world, a systematic communication system is imperative. PBX phone systems are an affordable solution for small and home offices. This advanced telecommunication alternative manages your business calls perfectly, highlighting your enterprise as a reliable and well-run one.

Pbx Phone Systems - Quality Answering Services

PBX phone systems with quality answering services are beneficial for small businesses in that they help them grow and achieve a big business image in a cost-effective manner. Advanced hosted PBX phone systems are more functional and flexible than premise-based PBX systems. Innovative communication features improve business productivity by enhancing customer satisfaction.

Phone Answering Service

You might often have been frustrated with the huge volume of calls coming to your office, whether big or small. It is at this point that phone answering service can help you. The phone calls that you or your staff cannot answer in person can be handled efficiently with the help of a phone answering service. With the use of an automated answering service you can minimize your expenses, maximize your productive time and achieve goals at a faster pace.

Prepaid Versus Postpaid International Calling Cards

Maintaining an open line of communication with other people is an important aspect in any personò€™s life. It allows people to keep in touch with others, whether it is for business or for personal reasons. One way of being able to do this is by using international calling cards, which can be either prepaid or postpaid.

Preparing for a Conference Call? Five Key Pointers

With conference calls becoming increasingly popular as a means of conducting business meetings and making presentations, its important to pay some attention to the basic preparations before the actual voice conference is carried out.

Residential And Business Communication Needs

Communication is the basic need of every individual on Earth. Unlike the olden days when the communication options were very limited, today, with great advancements in technology there are many forms of communication available. We are of course living in an age of advanced communication and there are countless numbers of communication options to choose from. However, not all the communication options available today will satisfy the communication needs of everyone. In general communication options can be broadly classified as residential and business solutions.

Reverse Cell Phone Directory - is it Legal to Use One?

There are some methods of trying to find out who is behind an unknown cell phone number that will land you in trouble but using a reverse cell phone directory is not one of them.

Review of Samsung A870 (camera Phone)

Model Samsung A870 (Camera Phone)

Role of audio conferencing in boosting business

As the demand for time and cost efficient means of conducting business processes is increasing, technological advancements have been made to support the same. With passing days, many shifts and readjustments have been made in several arenas of business. For instance, the way meetings are held have evolved drastically in the wake of making them more effective and at the same time cost efficient.

Rural Business with Satellite Internet

When someone thinks of a successful businessperson the immediate image that most likely pops up in their mind is a city slicker with a fancy suit and a fancy laptop. While this might be the case a lot of times, there are plenty of other people occupying the place of a successful businessperson that differ quite dramatically from the city slicker image. Just because someone prefers the quite and scenery of country living does not mean they do not have what it takes to run a successful business, and satellite internet makes this sentiment truer than ever.

SMS marketing strategy the best communication tactic

In the modern age people doesnò€™t have much time to wait for a long time to listen or to read the various offers and special offers from different business organizations. They donò€™t have even much time to talk if it doesnò€™t seem to them to be much important. Therefore for the various business companies it has become a very difficult task to communicate with their probable customers. Therefore in this case there is the option of SMS marketing. With the help of this process there is no need for the company agents to visit the customers to let them know about the latest special offers and even it is beneficial for the customers also that they need not visit some local office to gather knowledge on some product.

Samsung D900 - Ultra Smart Slide Phone

By introducing the ultra-thin Samsung D900, Samsung has really given hard times to other competitors.. The Samsung D900 is one of a kind gadget, which is keenly loaded with compatible features. As such, the Samsung D900 is a part of the Samsung"s hot "Ultra Edition" collection, but it is bit different from others. With thickness only 12.9mm, you would certainly feel, as if you are carrying two credit cards. It weighs only 85 gm, as it has been perfected by soft touch plastic and its designing is also devoid of any metal. The Samsung D900 is beautifully wrapped in black colour, which is bit diluted by silver insertions.

Samsung OfficeServ is not a Bad Choice

If you are an organisation with fewer than 500 extensions and you are looking for a telephone system then the Samsung OfficeServ is quite a good choice actually. There are numerous areas where it will beat the competition hands down and this is born out by its success in winning market share. In this guide we will break the main plusses into some manageable chunks.

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