Page 138 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

EXERCISE 59 : Repair of LED Lights

Objectives

At the end of this exercise you shall be able to:
• check and identify the parts/components of LED lights
• test the circuit and all the components of defective of LED light step by step
• find the cause of defect and Replace the defective components
• repair and test the LED light.
Requirements

Tools/Equipments/Instruments
• Combination Plier 150 mm, • Multi meter Digital, 3 digit - 1 No.
1/2
insulated - 1 No. Materials/Components
• Connector screw Driver 100mm,
insulated - 1 No. • Defective LED Bulb/light Any rating - 2 Nos.
• Neon Tester 75mm, 500 V - 1 No. • PVC hook up wire 0.5 sq.mm - as reqd.
• Electrician knife Insulated - 1 No. • Capacitors AC/DC Any rating - as reqd.
• Wire stripper 100mm - 1 No. • LED Any rating - as reqd.
• Soldering iron 25 watts, 230 V - 1 No. • Soldering lead & flux - as reqd.
• De-soldering pump - 1 No.

Procedure

TASK 1: Check the parts & circuit of LED light
1 Draw the circuit diagram of LED light/bulb.

2 Identify the parts/components of LED light/bulb and study the circuit.
3 Test & observe the type of defect in LED light.

TASK 2: Repair of LED light / bulb
1 Check the loose connection / de-solder of wires and components in defective LED light.

2 Check for defective LED’s if any, and remove the same by de-soldering.
3 Dismantle the parts / components of LED light.
4 Test the driver circuit and check for damage of components if any.
5 Connect the driver with AC supply and check the voltage with multi-meter in each section.
6 Repair / replace the damaged components like capacitors, LED
7 After repair/replacement of defective components test the circuit with AC supply.

8 On successful working re-assemble the LED light and test once again with supply.

Safety precautions
1 Handle the LED light/bulb carefully.
2 Connect the capacitors with proper polarity.

3 Do not over heat the components while soldering.
4 Do not touch PCB while testing with AC supply.

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