Page 40 - CITS - Electrician - Trade Practical

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ELECTRICIAN - CITS

MODULE 3: Heating Effect, Cells and Batteries

EXERCISE 13 : To prepare the heating element & solenoid

coil

Objectives

At the end of this exercise you shall be able to
• calculate the length & resistance of nichrome wire to prepare the heating coil
• prepare the heating element and test the heating
• prepare the solenoid coil and check the magnetic effect of electric current

Requirements

Tools/Equipments/Instruments Materials/Components
• Combination plier (165mm, insulated) - 1 No. • Nichrome wire (24 SWG) - 2 meter.
• Side cutting plier • Bare copper wire ( 36 SWG) - 2 meter.
(150mm, insulated) -1 No. • PVC connecting wire (1.5 sq.mm) - as reqd.
• Neon tester (75mm, insulated) -1 No. • Plastic Bobbin - 1 No.
• Wire stripper (150 mm) -1 No. • Soldering lead - as reqd.
• Screw driver, insulated (150 mm) -1 No. • Soldering flux - as reqd.
• Soldering iron with stand • Porcelain heating plate - 1 No.
(25 W, 230 V) -1 No. • GI bare conductor (8 SWG) - 1 meter.
• 1 Ph. Auto transformer
(0-270 V, 10 A) -1 No.
• Digital Multi meter (3 digit) -1 No.
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Procedure

TASK 1: Prepare the heating element and test
1 Calculate the resistance of nichrome wire required to make heating coil of 1 KW, 230 V AC
2 Take required length of nichrome wire as per calculated value of resistance.

3 Wound the nichrome wire uniformly on GI bare conductor and prepare the heating coil.
4 Place the heating coil in the slots of porcelain heating plate and connect the end terminals to the connector.
5 Measure the resistance of heating coil and record it.
6 Connect the heating coil to the supply through auto transformer.
7 Switch ON the supply and slowly increase the voltage in auto transformer.

8 Observe the heat produced in heating coil.
9 Switch OFF the supply and disconnect the heating coil.

TASK 2: Prepare the solenoid coil and test

1 Fix the plastic bobbin vertically on wooden board.
2 Fix the nail tightly adjacent to the plastic bobbin.
3 Twist & tie one end of bare copper conductor tightly to the nail.
4 Now start winding of bare copper conductor uniformly on plastic bobbin and prepare the Solenoid coil

5 Make the solenoid coil of around 100 turns and wrap the insulating paper tightly on the coil.

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