Measurement of High Resistance by Loss of Charge Method problem No 2

TL;DR

This video explains how to measure high resistances using the loss of charge method and provides a step-by-step solution to a specific problem.

Transcript

hello friends in this video we are going to solve a problem based on the measurement of high resistance using loss of charge method so let us start with a problem so a question is that a cable is tested by the loss of charge method using a ballistic galvanometer with the following results so uh the loss of charge method it is used for measuring the... Read More

Key Insights

• ✋ The loss of charge method is a useful technique for measuring high resistances or insulation resistance.
• ⚡ The deflection on the galvanometer indicates the voltage across the unknown resistance and capacitor.
• 🌸 Using the formula for the loss of charge method, the insulation resistance of a cable can be calculated.
• ❓ When the insulation resistance is in parallel with another resistance, the equivalent resistance can be determined.
• 🥳 The ratio of the equivalent resistance and the insulation resistance can be calculated to find the value of the insulation resistance.
• 🌸 The given problem demonstrates the step-by-step calculation of the insulation resistance using the loss of charge method.
• 📣 The value of the insulation resistance is found to be 5 mega ohm.

Questions & Answers

Q: What is the purpose of the loss of charge method?

The loss of charge method is used to measure the high resistances or insulation resistance of a cable.

Q: How are the measurements indicated in the loss of charge method?

The deflection on the ballistic galvanometer indicates the voltage across the unknown resistance and capacitor.

Q: How do you calculate the insulation resistance of the cable?

The insulation resistance can be calculated using the formula: r = 0.4343 * t / c * log10(capital v / small v).

Q: How can you find the equivalent resistance when the insulation resistance is in parallel with another resistance?

The equivalent resistance (r dash) can be calculated as r * 10 mega ohm / (r + 10 mega ohm).

Summary & Key Takeaways

• The loss of charge method is used to measure the high resistance or insulation resistance of a cable.

• The deflection on the galvanometer indicates the voltage across the unknown resistance and capacitor in the circuit.

• By using the given measurements and the formula for the loss of charge method, the insulation resistance of the cable can be calculated.