DCS System: A DCS System is preferred over a central computer system for the following reasons. Central Computer System (CCS) exposes the plant to the risk that the system might fail. This can be minimized by…
DC Traction using Semiconductor Chopper Controlled DC Motors: Chopper control has replaced resistance control in all dc traction schemes, such as 1500 V dc main line and suburban traction, 750 V dc underground traction and…
DC Standard Differential Voltmeter: A basic DC Standard Differential Voltmeter can be operated in different modes. The three basic modes of operation are as a dc voltage standard, as a dc differential voltmeter, and as…
DC Shunt Motor Starter Design: Maximum current that a DC Shunt Motor Starter Design can safely carry during starting is limited by the maximum current that can be commutated without sparking. For normally designed machines,…
DC Series Motor Starter Working Principle: The series motor starter serves the same purpose as the three- and four-point starters employed with shunt and compound wound motors. However, series motor starter has different internal and…
DC Motor Speed Control: In the foregoing sections we discussed the torque-speed characteristics of dc motors, bringing out the effects of armature voltage variation and field current on them. The discussion also applies to the…
DC Motor Reversing Switch Diagram: DC Motor Reversing Switch Diagram is shown in Fig. 5.34(a). A fully-controlled rectifier feeds the motor through a reversing switch RS which is used to reverse the armature connection with…
DC Motor Losses and Efficiency: The Losses and Efficiency of a transformer have been studied in earlier lesson. As in the case of transformers, it is more accurate to determine the DC Motor Losses and…
DC Motor Electric Brakes: DC Motor Electric Brakes - While operating electrical drives it is often necessary to stop the motor quickly and also reverse it. In applications like cranes or hoists the torque of…
DC Motor Control through Converters: DC motor control is conveniently and efficiently achieved by phase-controlled converters wherein the ac input voltage is converted to a controlled dc output. The commutation process, the transfer of current from…
