Figure 4 shows a DC shunt motors which are normally used where field current is kept constant and armature voltage is changed to obtain the desire speed. The feedback is taken by using a speed tachometer. This generate voltage proportional to speed which is compared with voltage required to the desire speed, there the difference is used to change the input to controller with cumulatively changes the speed of the motor as required. Draw a block diagram to represent the system in Figure 3. You may use “Desire speed” and “Actual speed” as the input and output of your block diagram. Your block diagram should contain “Load”, “Amplifier”, “Tachometer” and “Armature”. Label your diagram correctly.