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The amount of knowledge an electrician must possess to be able to install and troubleshoot control systems in today's industry has increased dramatically in recent years. A continuous influx of improved control components allows engineers and electricians to design and install even more sophisticated and complex control systems. Industrial Motor Control presents the solid-state devices common in an industrial environment. This is intended to help the Learner understand how many of the control components operate, such as solid-state relays, rectifiers, SCR drives for direct current motors, vari able frequency drives for alternating current motors, and the inputs and outputs of programmable controllers. Although most electricians do not troubleshoot circuits on a component level, a basic knowledge of how these electronic devices operate is necessary in understanding how various control components perform their functions.
The influx of programmable logic controllers into industry has bridged the gap between the responsibilities of the electrician and the instrumentation technician. Many industries now insist that electricians and instrumentation technicians be cross-trained so they can work more closely together. Industrial Motor Control helps fulfill this requirement. Many of the common control devices found throughout industry are also discussed from a basic instrumentation standpoint by providing information on analog sensing of pressure, flow, temperature, and liquid level.
The section on motor installation has been updated to reflect changes in the 2014 National Electrical Code, and a unit that instructs Learners in basic troubleshooting techniques has been included. The sections have been rearranged to present the information in a different order. This rearrangement was done to reflect recommendations made by instructors that use the text.
Industrial Motor Control presents many examples of control logic and gives the Learner step by-step instructions on how these circuits operate.
There are examples of how ladder diagrams can be converted into wiring diagrams. This is the basis for understanding how to connect control circuits in the field. The concept of how motor control schematics are numbered is thoroughly discussed. Learners are also given a set of conditions that a circuit must meet, and then that circuit is developed in a step-by-step procedure. Learning to design control circuits is a very effective means of learning how circuit logic works. It is impossible to effectively troubleshoot a control circuit if you don't under stand the logic of what the circuit is intended to do.
Industrial Motor Control is based on the results of extensive research into content, organization, and effective learning styles. Short sections help the Learner to completely understand the content before progressing to the next subject, and they permit the instructor to choose the order of presentation. Each section contains extensive illustrations, which have been designed for maxi mum learning. Color is used to help the Learner understand exactly what is being conveyed in a particular illustration.
•The most commonly used solid-state devices are thoroughly described, in terms of both operation and typical application.
• Information on analog devices that sense pressure, flow, and temperature has been added to help bridge the gap between the industrial electrician and the instrumentation technician.
•DC and AC motor theory is included so Learners will understand the effects of control circuits on motor characteristics.
•The Guide covers the operating characteristics of stepping motors when connected to either DC or AC voltage.
•Detailed instructions are given for connecting motors in the field, including the size of conductors, overload relays, and fuses or circuit breakers. All calculations are taken from the National Electrical Code.
•The principles of digital logic are described in sufficient detail for Learners to understand programmable controllers and prepare basic programs.
•A step-by-step testing procedure for electronic components is provided.
• Starting methods for hermetically sealed single-phase motors include the hot-wire relay, solid-state starting relay, current relay, and potential relay.
•Extensive coverage on overload relays and methods of protecting large horsepower motors is provided.
•There is extensive coverage of variable frequency drives.
•Solid-state control devices, in addition to electromagnetic devices, are thoroughly covered.
•Basic electronics is not a prerequisite for this Guide. Sufficient solid-state theory is presented to enable the Learner to understand and apply the concepts discussed.