1. AC and DC meters

2. Ammeter
Ammeter is an electrical measuring device, which is used to measure electric current through the circuit.
CONNECTION OF AMMETER IN CIRCUIT
An ammeter is always connected in series to a circuit.
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3. Ammeter Ammeter is a low resistance galvanometer
It is used to measure the current in a circuit in amperes
Galvanometer can be converted into an ammeter by using a low resistance wire in parallel with the galvanometer
the resistance of the wire depends upon the range of the ammeter
As shunt resistance is small the combined resistance of the galvanometer & the shunt is very low hence the ammeter has much lower resistance than galvanometer
An ideal ammeter has zero resistance

6. Voltmeter
Voltmeter is an electrical measuring device, which is used to measure potential difference between two points in a circuit.
CONNECTION OF VOLTMETER IN CIRCUIT
Voltmeter is always connected in parallel to a circuit.
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8. Voltmeter Volt meter is a high resistance galvanometer
It is used to measure the potential difference between two points of a circuit in volts
A galvanometer can be converted into a volt meter by using a high resistance in series with the galvanometer
The value of resistance depends upon the range of the volt meter
For voltmeter a high resistance, R is connected in series with the galvanometer therefore resistance of voltmeter is very large as compared to that of galvanometer
The resistance of an ideal voltmeter is infinity

12. Ohmmeter
The purpose of an ohmmeter, is to measure the resistance placed between its leads.
This resistance reading is indicated through a mechanical meter movement which operates on electric current.
The ohmmeter must then have an internal source of voltage to create the necessary current to operate the movement
Also have appropriate ranging resistors to allow just the right amount of current through the movement at any given resistance

13. Simple ohmmeter circuit

14. Multimeter
A multimeter is a device used to measure electrical current, voltage, and resistance. A multimeter combines several electrical meters into one handheld unit.
Basic multimeter models can measure voltage, current and resistance.
Advanced models can also measure temperature, inductance, capacitance, duty cycle and frequency.
They can also test diodes and transistors.
Some even work as an oscilloscope.
The two main types of multimeter are digital and analogue

16. Thank You..