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(d) Automatic sprinkler system for fires. The controller is On/Off and the control i feedback with respect to temperature., M, D, A: temperature element/controller TE/C. Usually a bi-metallic strip that pushes the latch on the mechanism holding the slice of bread. The bread is released and the heating element de-energized when the temperature reaches the value set by the set point. TE/CSP (c) Toaster. The controller is On/Off and the control is feedback on the temperature variable. M: Temperature element TE, usually a gas-filled bulb D: Temperature controller TC. A: Solenoid S that operates the heating element in the oven (b) Cooking oven. TETC S SP The controller is On/Off and the control is feedback. M: Temperature element TE in thermostat TE/C D: Mercury switch in thermostat TE/C A: Solenoid S that turns unit (AC/H) on and off. TE/C S AC /H SP (a) House air-conditioning/heating. Identificaton of the M-D-A components, controller type, instrumentation diagram, and type of control. Problem 1-1. Automation in daily life. Smith & Corripio, 3rd edition Water main TE/C M, D, A: temperature element/controller TE/C, a rod that gives to the water pressure at a set temperature, allowing the water to spray over the fire. The controller is On/Off with single action, and the control is feedback. (e) Automatic cruise speed control. ST SC SP S Air Engine Transmission M: Speed sensor and transmitter ST on the transmission D: Speed controller SC A: Damper on air intake to the engine throttles the air varying the power delivered by the engine Controller is regulating and control is feedback. (f) Refrigerator. TE/C S SP M: temperature sensor TE, usually a gas-filled bulb D: Temperature controller C, mechanically linked to the sensor A: Solenoid S that turnsd the refrigeration compressor on and off The controller is On/Off and the control is feedback. Excerpts from this work may be reproduced by instructors for distribution on a not-for-profit basis for testing or instructional purposes only to students enrolled in courses for which the textbook has been adopted. Any other reproduction or translation of this work beyond that permitted by Sections 107 or 108 of the 1976 United States Copyright Act without the permission of the copyright owner is unlawful. Smith & Corripio, 3rd edition Problem 1-2. Automatic shower temperature diagram. TETC Hot water Cold water S SP M: temperature sensor TE, a gas-filled bulb D: temperature controller TC, mechanilly integrated to the sensor, but with a signa output A: solenoid operated control valve on the hot water line. The cold water valve is operated manually. Excerpts from this work may be reproduced by instructors for distribution on a not-for-profit basis for testing or instructional purposes only to students enrolled in courses for which the textbook has been adopted. Any other reproduction or translation of this work beyond that permitted by Sections 107 or 108 of the 1976 United States Copyright Act without the permission of the copyright owner is unlawful.
