**Experiment No. :** 2

**Experiment Name : **

Use of LCR-Q meter to measure the value of a given capacitor and inductor.

**Objective : **

To use LCR-Q meter to measure the value of a given capacitor and inductor.

**Theory : **

**LCR-Q meter :** LCR-Q meter is a measuring instrument which is used to measure the value of inductance (L), capacitance (C), resistance (R) and the Q-factor or quality factor of inductor and D-factor or dissipation factor of capacitor. It can measure inductance in the range of 200.00 Î¼H to 2000.0 H, capacitance in the range of 2000.0 pF to 2.000 mF and the resistance in the range of 20.000 Î© to 200.0 MÎ©.

When measuring capacitance selecting, the right frequency is important in obtaining the most accurate measurement results. Generally, 1 kHz test frequency is used to measures capacitance of 0.01 Î¼F or smaller. For capacitors that are 10 Î¼F or larger, a lower frequency of 120 Hz is used.

Typically, a 1 kHz test frequency is used to measure inductors that are used audio and RF circuits. And a 120 Hz test frequency is used to measures inductors that are used for filter chokes in power supply.

**Some Properties of Capacitor :** These are some basic properties of a capacitor.

- It is a passive element
- It can store electrostatic energy
- It can oppose the change in voltage
- It can pass AC and block DC
**Capacitive Reactance (X**– Property by the virtue of which it can oppose the flow of current_{C})- Capacitive Reactance (X
_{C}) = 1 / (2Ï€ f C). Unit of X_{C}Ohm (Î©) - Capacitance is measured in pico Farad, micro Farad, milli Farad (pF, ÂµF, mF )
**Q-Factor –**A capacitor with small series resistance R associated within. The Q-factor or the**quality factor**of a capacitor at the operating frequency Ï‰ is defined as the ratio of the reactance of the capacitor to its series resistance. Q = (X_{C}/ R). It is a dimensionless quantity.**D-Factor –**The**dissipation factor**of a capacitor is the power loss when AC is applied through the capacitor. This power is either absorbed by the dielectric material or internal/external resistance. Externally, the leads, pads, and solder all lead to an increase in resistance.**D = R/X**or_{C}**D = 1/Q**

**Some Properties of Inductor :** These are some basic properties of an Inductor.

- It is a passive element
- It can store electromagnetic energy
- It can oppose the change in current
- It can pass AC and block DC
**Inductive Reactance (X**– Property by the virtue of which it can oppose the flow of current_{L})- Inductive Reactance (X
_{L}) = (2Ï€ f L). Unit of X_{L}Ohm (Î©) - Inductance is measured in micro Henry, milli Henry, Henry (ÂµH, mH, H)
**Q-Factor –**The Quality factor or the Q factor of an inductor at the operating frequency Ï‰ is the ratio of reactance of the coil to its resistance. Every inductor possesses a small resistance in addition to its inductance. The lower the value of this resistance R, the better the quality of the coil.- Q = (X
_{C}/ R). It is a dimensionless quantity.

**Circuit Diagram :**

**Observation Table :**

**Apparatus used:**

- We should discharge the capacitor before measuring the capacitance.
- To get accurate result we should calibrate the LCR-Q meter before measurment.