Motor starters generally fall into two categories: full-voltage or reduced-voltage. The choice of which type of starter to use depends on various factors, such as current-carrying capacity of plant wiring, ability of plant power supplies to absorb power transients, size of the motor, and other special control requirements. The first type to be covered is the full-voltage starter.
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Full-voltage starters, sometimes referred to as ``across-the-line`` starters, are the most widely used type of starter. A starter of this type, shown in ```Figure 1```, directly connects the motor leads and line leads together through either a manual starter or the main line contacts of a magnetic starter and does not provide any means of reducing the applied voltage or limiting the starting current. The full-voltage starter is used on almost all three-phase, squirrel-cage, and single-phase machines. The use of this type of starter for squirrel-cage motors is limited by the strain imposed on the installed wiring systems and by the starting current and torque when the motor is first energized. Whenever the starting of a motor at full voltage would cause serious and unacceptable voltage transients or excessive torque when unneeded, reduced-voltage starters are used to reduce the starting transients. There are, however, other reasons for using this type of control. The effect on the equipment must be taken into account in the selection of motor starters. When a large motor is started across the line, it puts a tremendous strain or shock on such things as gears, fan blades, pulleys, and couplings. When the load is heavy and hard to bring up to speed, reduced-voltage starting may be necessary. Belt drives on heavy loads are apt to have excessive slippage unless the torque is applied slowly and evenly until full speed is...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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