A light-seeking control system, used to track the sun, is shown in Figure P1.5. The output shaft, driven by the motor through a worm reduction gear, has a bracket attached on which are mounted two photocells. Complete the closed-loop system so that the system follows the light source.

A d.c. shunt motor after running for several hours on constant voltage mains at 400 V takes a field current of 1.6 A. If the temperature rise is known to be 40°C, what value of extra circuit resistance is required to adjust the field current to 1.6 A when starting from cold at 20°C? Temperature coefficient = 0.0043/°C at 20°C. [36.69 0]

A shunt DC motor is supplied by 520V terminals voltage and is used to supply a mechanical load with rotating speed of 1000rpm. The armature is wave-wound and has 500 conductors. The useful flux per pole is 0.03Wb and there are 4 poles (2 pairs of poles). The armature resistance is 0.4 Ohms. Calculate: 1.The internal emf of the motor. 2.The armature current.   CLEAR AND CORRECT OR DISLIKE

A shunt-wound DC motor with the field coils and rotor connected in parallel (Figure 1) operates from a 130 V DC power line. The resistance of the field windings, R. is 208 n. The resistance of the rotor, R,, is 4.90 1. When the motor is running, the rotor develops an emf E. The motor draws a current of 4.46 A from the line. Friction losses amount to 45.0 W Part C Compute the emf E. • View Available Hint(s) Tematates Symbols undo redo Tese keyboard shortcuts Help V Submit Part D Compute the rate of development of thermal energy in the field windings. Express your answer in watts. > View Available Hint(s) Templates Symbols undo redo Teset keyboard shortcuts Help Pan,windings = Figure W K 1 of 1 Submit Part E Compute the rate Pin.rotor of development of thermal energy in the rotor. R ER, Express your answer in watts. > View Available Hint(s) Templates Symbols undo redo teset keyboard shortcuts help Pinrotor=