Electrical Power Systems Technology

390 Electrical Power Systems Technology Under excitation—operates at a lagging power factor (inductive ef- fect). Over excitati ...

Mechanical Systems 391 Note the variation of stator current drawn by the synchronous motor as the rotor current varies. You shou ...

392 Electrical Power Systems Technology tion from one location to another without any direct mechanical linkage. Synchro systems ...

Mechanical Systems 393 line voltage is applied to the rotors of both the generator and motor. The stationary coils, or stator wi ...

394 Electrical Power Systems Technology in a clockwise direction will cause a corresponding change in the motor unit. If calibra ...

Mechanical Systems 395 conveyor-belt control units, in spindle-speed control in machine-tool op- erations, and in disk or magnet ...

396 Electrical Power Systems Technology cific signal polarity is applied. Also, the amount of torque developed by a servomotor m ...

Mechanical Systems 397 watts.) Then, P pf = —— VA where: pf = the power factor of the circuit, P = the true power in watts, and ...

398 Electrical Power Systems Technology tors do not operate at undervoltage or overvoltage conditions. Considerations for Mechan ...

Mechanical Systems 399 Universal motors (AC/DC) motors used for many types of portable tools and appliances, such as electric d ...

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401 UNIT V Electrical Power Control Systems In this unit, electrical power control systems are studied. The funda- mentals of el ...

402 Electrical Power Systems Technology Figure V. Electrical power systems model Power Control (Chapter 15) Operational Power Co ...

Unit Objectives 403 Start-Stop Control with Safe-Run Feature Start-Stop Control with Run-Jog Feature Start-Stop-Jog Control Forw ...

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405 Chapter 15 Power Control The control of electrical power is a very important part of electrical power system operation. Cont ...

406 Electrical Power Systems Technology Reduced-Voltage Starting Control Relay Safety Switch Solenoid Timing Relay Switches SPST ...

Power Control 407 formance of various electrical power control equipment. These standards provide information concerning the vol ...

408 Electrical Power Systems Technology electric power circuit. Controller—A device or group of devices that systematically cont ...

Power Control 409 Pushbutton Station—A housing for the pushbuttons that are used to con- trol equipment. Reduced-voltage Starter ...