DOMESTIC ELECTRONIC APPLIANCES
Name of Sector Electronics & Hardware Name of Module Maintenance Of Domestic Electronic Appliances
Minimum Age 18 Years Duration of Course 6 Months
ADU Code ELC701

B.E./ B.Tech. in Electronics / Electronics & Telecommunication/Electronics & Communication with one year experience in the relevant field

(OR)

Diploma in Electronics/ Electronics & Telecommunication / Electronics & Communication from recognized board of technical education with two years experience in the relevant field.

(OR)

NTC/NAC in the relevant trade with three years’ experience respectively in the relevant field



After completion of the module the participant would be able to maintain and repair of Power supply, inverter and UPS install and repair washing machine, repair microwave oven, stream iron, electric rice cooker, electric kettle and mixer grinder.

Objectives :

Testing of electrical parameters, cables and measurements.

Select the proper instrument for suitable measurement.

Identify and test passive and active electronics components.

Practice soldering and de-soldering of various types of electrical and electronics components.

Trouble shoot the faults in the given power supply circuits.

Identify various Input and output sockets/connectors of the given UPS.

Identify various functional blocks/major components/ICs in the given UPS.

Monitor, measure major test points and Test the capacity of the given UPS and rectify the faults.

Identify and test various mechanical and electrical modules of the given appliances.

Identify electronics parts/components/modules of the given appliances.

Aware of models of different appliances and features.

Use reference manuals and identify the information required to service the appliances.

Practice the standard troubleshooting procedures as suggested in the product manuals.

Install the given appliance as recommended by manufacturer.



Practical Competencies Underpinning Knowledge (Theory)

Basics of electricity and Electrical Cables

  • Practice procedure for electrical and personal safety measures
  • Identify the Live, Neutral and Earth on power Socket
  • Construct a test lamp and use it to mains healthiness
  • Use a Tester to monitor AC power.
  • Measure the voltage between the neutral and ground and rectify earthing
  • Identify and test different ac mains cables
  • Skin the electrical wires /cables
  • Measure the gauge of the wire using SWG
  • Make the mains cable for termination
  • Identify the primary and secondary cells
  • Measure and test the voltages of the given cells/battery using analog and digital Multi-meter
  • Charge and discharge the battery
  • Use a hydro-meter to measure the specific gravity of the secondary battery


Basic terms electric charges, Potential difference, Voltage, Current, and Resistance. Basics of AC & DC. Terms such as positive cycle, negative cycle, Frequency, Time period, RMS, Peak value , peak to peak, instantaneous values, Insulators, conductors and semiconductor. Different type of electrical cables and their specifications.

Multi-meter

  • Cleaning the switch contacts using switch cleaning solution.
  • Testing the fuse.
  • Use the analog and digital Multi-meter to measure the DC voltage by doing measurement at the test points provided.
  • Use the analog and digital Multi-meter to measure AC voltage measurement by doing measurement at the test points provided.
  • Adjust the zero adjustment screw for proper zero setting with the help of a screw driver before using Multi-meter.
  • Replace the battery in the Multi-meter.
  • Replacing the open Fuse with correct rating


Precaution to be taken in handling an analog Multi-meter.

Study of different controls on Multimeter

Principle of operation of Analog Multi-meter.

Precaution to be taken in handling digital Multi-meter

Frequently occurring problems in Analog multimeters and the remedial measures

Precaution to be taken in handling digital Multi-meter,

Familiarization with operation controls of digital Multi-meter

Principle of operation of digital Multi-meter.

Frequently occurring problems in Digital multimeters and the remedial measures

Basic Electronics Components

  • Identify the different types of resistors
  • Measure the resistor values using colour code and verify the reading by measuring in multi-meter
  • Identify the power rating using size
  • Identify different inductors and measure the values using LCR meter
  • Identify the different capacitors and measure capacitance of various capacitors using LCR meter
  • Dismantle and identify the different parts of a relay
  • Identify different types of mains transformers and test them
  • Identify the primary and secondary transformer windings
  • Measure the primary and secondary voltage of different transformers


Resistor-definition, types of resistors, their construction & specific use, color-coding, power rating.

Types of inductors, specifications and applications.

Types of capacitors, specifications and applications

Working principle of a Transformer,

Specifications of a transformer, Step-up, Step down and isolation transformers

Fuse – types, use of fuses and its rating.

Power supply

  • Testing of active components
  • Practice soldering and de-soldering techniques
  • Assemble and test– half wave, full wave & bridge rectifier circuits with and without filter.
  • Identify the different types of fixed positive and negative regulator ICs (78/79 series)
  • Identify the pins
  • Construct a fixed voltage regulator using 78xx/79xx series ICs
  • Construct a variable voltage regulator using LM 723.
  • Observe the output voltage of different IC regulators by varying the input voltage


Basic Electronics active components, testing of components,

Working of half wave, full wave and bridge rectifier circuits.

Voltage Regulator circuit.

Applications of transistor – its uses

MOSFET – precautions when handling.

DIAC, SCR, TRIAC - application

Identify the pin diagram of Voltage regulator ICs

UPS/Inverter

  • Installation of UPS and Inverters
  • Maintenance of batteries
  • Dismantle the UPS and identify the major parts
  • Testing of major components
  • Testing of power modules
  • Charging, discharging and testing of batteries.


Various types of batteries used in UPS and Inverters and their maintenance.

Different types of inverter, UPS, Working principle, specifications, explanation with the help of block diagram.

SMPS

  • Dismantle the given SMPS and find major sections/ ICs components.
  • Measure voltages at vital points
  • Identify various input and output sockets / connectors of the given SMPS.
  • Repairing of SMPS, simulating various faults diagnosing and rectifying it.


Block Diagram of Switch mode power supplies and their working principles

Washing machine

  • Installation of front load washing machine
  • Installation of top load washing machine
  • Identify the internal and external parts of semi-auto washing machine
  • Identify the internal and external parts of fully automatic washing machine
  • Operate semi–automatic washing machine
  • Operate fully–automatic washing machine
  • Rectify the fault leading to not working of control panel switches.
  • Rectify the fault leading to not working of pulsator / agitator.
  • Rectify the fault leading to spin drier not working.
  • Rectify the fault leading to one side rotation of motor.
  • Rectify the fault leading to water inlet and outlet valves.


Washing M/c: different types of machines, washing techniques, parts of manual, semi automatic and fully automatic machines, basic working principle of manual, semi automatic and fully automatic machines, study the working of motors, different types of timers, power supply circuits.

Microwave oven

  • Identify the internal and external parts of micro wave oven.
  • Identify the different touch pad controls their functions
  • Testing of high voltage diode.
  • Identify the HV capacitor and discharge it.
  • Rectify the fault leading to fuse blows off when cooking is initiated.
  • Rectify the fault leading to not responding of touch switches.( front panel )
  • Rectify the fault leading to dead set.
  • Rectify the fault leading to long cook time.
  • Precautions – importance of interlocking switch in performing maintenance


Microwave oven: Different types of oven, study the various functions of Oven, Electrical wiring diagram of microwave oven, working of Power supply.

Steam Iron

  • Dismantle and identification of various parts, wiring, tracing of various controls, Electronic circuits in steam Iron
  • Identify the faults in steam iron & rectify


Principle of electric iron, parts of steam iron, thermostat heat controls.

Electric Rice cooker

  • Identify various components of Electric rice cooker, controls and trace the circuit and rectify the simulated faults.


Principle of working of rice cooker.

Various parts & functions of rice cooker, temperature control and timer unit.

Electric kettle

Identify various components of Electric kettle, controls and trace the circuit and rectify the simulated faults.



Principle of working of rice cooker.

Various parts & functions of rice cooker, temperature control and timer unit.

Mixer & Grinder

  • Dismantle and identification of various parts, wiring, tracing of various controls, Electronic circuits in various types of Mixers/grinders
  • Identify the faults in various types of Mixers/grinders & rectify


Various parts & functions of Mixer/Grinder, speed control circuit & automatic over load protector.