Electrical Power Systems Technology

410 Electrical Power Systems Technology Figure 15-1. Common power control symbols (Courtesy Furnas Electric Co.) ...

Power Control 411 should become familiar with the symbols that are used for various types of toggle switches and with the contro ...

412 Electrical Power Systems Technology It will open a circuit when it is depressed. The NO pushbutton is open until it is manua ...

Power Control 413 vice. The electrical current developed as a result of the mechanical move- ment is used to limit movement of t ...

414 Electrical Power Systems Technology Float Switches Float switches are used when it is necessary to control the level of a li ...

Power Control 415 are start/stop control or the forward/reverse/stop control of electrical motors. Contacts are moved as the han ...

416 Electrical Power Systems Technology an excessive amount of current. Another type of motor starter is the magnetic starter, w ...

Power Control 417 of starter provides starting, stopping, and overload protection similar to that of a magnetic contactor. Howev ...

418 Electrical Power Systems Technology motor, and the type of power distribution (single-phase or three-phase). For example, a ...

Power Control 419 Classes of Motor Starters The types of motor starters that are commercially available are di- vided into five ...

420 Electrical Power Systems Technology and circuit breakers mounted in a common enclosure. They are used on systems of 600 volt ...

Power Control 421 Motor-controller Enclosures The purpose of a motor-controller enclosure is obvious. The operator is protected ...

422 Electrical Power Systems Technology cal Code for metal dust, carbon black, coal, coke, flour, starch, or grain dusts. The en ...

Power Control 423 “pickup” or “make” current. The current through the relay coil that al- lows the magnetic field to become weak ...

424 Electrical Power Systems Technology atively inexpensive and small in size. Many small, general-purpose re- lays are mounted ...

Power Control 425 operations. A typical application would be as follows: (1) a “start” push- button is pressed, (2) a timing rel ...

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427 Chapter 16 Operational Power Control Systems Chapter 15 dealt with the equipment used for electrical power con- trol. Now, t ...

428 Electrical Power Systems Technology Single-phase AC Motors DC Motors Motor Starting Protection Dynamic Braking Speed Control ...

Operational Power Control Systems 429 circuit will operate just like the circuit of Figure 16-1. The “jog” position is used so t ...