Page 46 - CITS - Electrician - Trade Practical

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ELECTRICIAN - CITS

EXERCISE 16 : Grouping of Cells

Objectives

At the end of this exercise you shall be able to
• identify the different types of primary cells and measure the EMF
• make the series & parallel connection of cells
• check the voltage & current in series and parallel connection of cells
• calculate internal resistance of cell.

Requirements

Tools/Equipments/Instruments • DC Voltmeter (0-15 V) - 1 No.
• Combination plier (165mm, insulated) - 1 No. • DC milli Ammeter (500 mA) - 1 No.
• Connector screw driver (100mm) - 1 No. Materials/Components
• Wire stripper (100mm) - 1 No.
• Digital Multi meter (3 digit) - 1 No. • Connecting wire (1.0 sq.mm) - As reqd.
1/2
- 8 No’s.
• Primary cells (1.5 V)
• Variable resistance (0-10 Ω) - 1 No. • Cell holder - 1 No.
Procedure

TASK 1: Connect the cells in series and test the voltage & current
1 Draw the circuit diagram of series / parallel connection of cells.

2 Connect the cells in series as per circuit diagram.
3 Close the switch and measure the total voltage and current in the circuit.
4 Measure the voltage drop and calculate internal resistance in the cells.
5 Note down the measured values and record in tabular column.

TASK 2: Connect the cells in parallel and test the voltage & current
1 Connect the cells in parallel as per circuit diagram.
2 Close the switch and measure the total voltage and current in the circuit.
3 Measure the voltage drop and calculate internal resistance in the cells.
4 Note down the measured values and record in tabular column.

5 Compare and differentiate between series & parallel connection of cells.
Safety precautions
• Use proper and insulated tools.
• Connect the cells with proper polarity.

• Take the meter readings correctly.
• Do not short the terminals of cells

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