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In an induction motor is a voltage that on several (connected up to about 6 times basis) of its rated current. Since the charge is accelerated, the available torque drops usually rises a little, then a maximum, while the current remains high until the motor reaches full speed.

In contrast, if a VFD starts a motor, applies a first low frequency and voltage to the motor. The frequency is from 2 Hz or less. This will avoid such a low frequency of the high inrush current, that occurs when the engine simply by applying the utility (mains) voltage started by turning a switch. After starting the VFD, and increases the frequency of the applied voltage at a controlled rate or be strengthened to accelerate the load without drawing too much power. This method usually begin to develop an engine to 150% of rated torque, while the VFD is income of less than 50% of the rated current of the power system in the low speed range. A VFD can be adjusted in order to produce a claim to 150% torque from standstill to full speed.
[16] Note however that the engine cooling is generally not good at slow speed. He works at low speeds, even with nominal torque over long periods is not possible due to overheating of the engine. If continuous operation at high torque at low speeds requires external fan is required. Please check with the manufacturer of the engine and / or VFD.  In principle, the current in the side of the motor is directly proportional to the torque generated and the voltage at the motor is directly proportional to the actual speed, while the network side, the voltage is constant, the mains current is directly proportional to the load on the engine , which the user interface or CN C, where N is the torque and speed (taking into account the losses will be neglected so that in this discussion.)

(A) n is the network (network) and for m motor (2) C shows the torque [Nm], the voltage U [V], that A] and N [for the speed [rad / s] we neglect the losses at the moment: Un.In Um.Im = (not draw the same grid and the motor) Um.Im Cm.Nm = (= motor mechanical power from the electric motor) In view of the United Nations a constant voltage (will) concluded : In Cm.Nm = / UN line that is in progress (network) is in direct proportion to engine power.

With a VFD, the shutdown is just the opposite, that the boot sequence. The frequency and the voltage at the motor is increased at a controlled rate. If the frequency tends to zero, the motor stops. A small amount of braking torque available to slow the load a little faster than if it stops the engine was turned off and just let the others. additional braking torque can be obtained controlled by a transistor) by the addition of a brake circuit (resistance in order to dissipate the braking energy. With recifiers four quadrants (Active Front End), the VFD is to stop the burden of applying a pair of reverse and back to the mains.

Few companies take advantage of new technologies in the first and the one exception with the new LG Super Multi Blue Player, the HD-DVD HD-DVD and Blu-ray seems.

This is according to a U.S. journalist today.
Super Multi Blue player has made on the recognition and praise for the wide dissemination of this opportunity for peace between the HD-DVD by Toshiba and Sony, the Blu-ray field was obtained. Although both formats on a similar technology that may be in a position to data on a disc can encode much more than others, with a standard DVD player, CD-player gaming is trivial format to another format. The result was a format war that many consumers are afraid to buy the players in all sizes, the fear of loss of art. Because of this fear of losing the purchase of a technology Super Multi Blue Player is certainly a risk that, no matter who the format, or read the end, mp4 rip dvd to documents wins softwarewill implanted device.

The main problem with the Super Multi Blue Player is the element which is too expensive. It is true that at a sale price of just under 1,200, many consumers are afraid to go shopping. One argument to explain why this device is that it is too expensive for the price of DVD standards. The article says, noted that the original DVD technology was much more important, the technology of HD DVD is superior, the technology of the DVD-standard DVD technology.

Ultimately, the article says, is the Super Multi Blue Player is not only a lot more money than a standard DVD player.

If a price of $ 1,200 may be too high for many consumers, the reporter seemed to be the real problem to lose. The real problem is the Super Multi Blue Player, the costs, if the difference between it and Blu-ray or HD DVD is worth the peace of mind of the consumer, who knows, or has not won, when has a machine from Sony and Toshiba surpassed indeed all those who have a clue. A fact that the idea that the Super Multi Blue Player supports can be profitable, it is much less capable of Blu-ray and HD-DVD is sold separately. But in practice the possibility of introducing lower prices for Blu-ray eliminated later this year.

So the question is not worried, but the cost of devices such as the Super Multi Blue Player can be downloaded faster than the HD-DVD and Blu-ray.

Another problem with the Super Multi Blue for Sony is that it is necessary with an HDMI cable to be connected to an HDTV. In addition, the device has features that do not block the reading of a normal CD or taking advantage of the many bonuses of HD-DVD.

If a journalist can be criticized for comparing the Super Multi Blue Player for DVD players, HES has hit the nail on the head with some of the shortcomings of existing measures.