Series OSS Code No. 104
(Theory) Paper III
Time allowed : 3 hours Maximum marks :40
Instructions : Attempt all questions.
1. (a) Explain the construction and working of a shaded pole motor. 6
Explain the procedure of components testing of a universal motor. 6
(b) Give the constructional details of the motor used in a ceiling fan. How will you reverse the direction of rotation of a ceiling fan ? 4
2. (a) Explain the construction and working principle of a mixer. Give its few uses. 5
(b) Describe in brief the working of a Manual Voltage Stabiliser with its circuit diagram. 5
3. (a) Explain the procedure of overhauling a washing machine. 4
(b) Explain the installation procedure of a desert cooler. Why is earthing of a desert cooler required ? 4
Describe in detail the procedure involved in the testing of a defective desert cooler. 4
4. (a) Describe in detail the procedure involved in the repair of a blower type room heater.
Give the constructional details of a bowl type room heater.
(b). Explain the common faults in a hair dryer. How will you rectify them ?
5. Explain the construction and working principle of a vacuum cleaner.
Describe the common faults in an electric hand drill. How will, you rectify them ?