How can you extend the range of an ammeter?
So to increase the range of ammeters we should have to connect low resistance in parallel so that equivalent resistance is lower hence to increase range of an ammeter we need to connect a suitable low resistance in parallel. Therefore option (A) is correct option .
What is the range of ammeter?
0-3 ampere
An ammeter has a range of 0-3 ampere and there are 30 divisions on its scales.
How do you extend the range of an ammeter and a voltmeter?
Detailed Solution. To increase the ranges of ammeter, we need to connect a small shunt resistance in parallel with ammeters. To increase the ranges of a voltmeter, we need to connect a high series of multiplier resistance in series with voltmeters. We can extend the range of ammeter by keeping a shunt resistance.
What is the formula for ammeter?
V=IR, here V is the potential difference across a resistance R through which a current I is flowing. The ammeter is connected in series with the circuit. So its reading will show the value of the current flowing in the circuit. Hence, the reading of the ammeter is equal to 1A.
Why do we need to extend the range of ammeter?
For example, a moving coil ammeter can measure currents 0-100mA. Thus it is impossible to measure high currents which are more than the measuring range of an instrument. Therefore, it is necessary to bring up these large currents to a value within the range of the instrument.
How range of ammeter can be extended using shunt?
Shunts: The range of an ammeter can be extended by connecting a low resistance, called shunt, connected in parallel with ammeter. A measuring instrument together with a shunt resistor becomes a ”new” device with an extended measurement range.
How do you extend the range of a voltmeter?
Multipliers: The range of voltmeter can be extended by connecting a high resistance, called multiplier in series with the voltmeter (Figure 2(b)). The multiplier limits the voltage drop so that it does not exceed the value of full scale and thus prevents from being damaged.
What is the range of the ammeter and the range of the voltmeter?
It is not possible to decrease the range of an ammeter. However, it can be increased by connecting a shunt (or low resistance) in parallel with the Ammeter. A voltmeter can have a maximum range of 0-20 V.
Why do we need to extend range of ammeter?
What is ammeter reading?
It is a instrument which helps in measuring ammeter the current in a circuit. By Ammeter reading we mean reading of the deflection of the magnetic needle which takes place because of the intensity of the magnetic field which takes place in the ammeter coil because of the amount of current flowing.
What is ammeter diagram?
Ammeter Circuit Diagram The construction of ammeter can be done in two ways like series and shunt. Once this device is connected in series in the circuit, then the total measurand current will flow through the meter. So the loss of power occurs within ammeter due to their internal resistance & the measurand current.
What does shunt mean in electrical terms?
A shunt is an electrical device that generates a low-resistance path for an electrical current. This enables the current to flow to an alternative point in the circuit. Shunts may also be referred to as ammeter shunts or current shunt resistors.
What can be used to extend the range of an ammeter?
Therefore, it becomes necessary that the current and voltage being measured be reduced and brought within the range of the instrument. There are four common devices used for the range extension of ammeter and voltmeter namely; shunts, multipliers and current and potential transformers.
How are ammeters used to measure electrical current?
Ammeters Measure Electrical Current. A meter designed to measure electrical current is popularly called an “ammeter” because the unit of measurement is “amps.” In ammeter designs, external resistors added to extend the usable range of the movement are connected in parallel with the movement rather than in series as is the case for voltmeters.
Why are shunts used in an ammeter and voltmeter?
Shunts are used for the range extension of ammeters. A shunt is a low-value resistance having minimum temperature co-efficient and is connected in parallel with the ammeter whose range is to be extended. The combination is connected in series with the circuit whose current is to be measured.
What kind of multipliers are used for moving ammeters?
Whereas in the case of moving iron ammeters, for the ranges up to 0 – 250 A, shunts are used and for the ranges higher than that, CTs are used. And also, in the case of moving iron voltmeters, for the ranges up to 0 – 750 V, multipliers are used and for the ranges higher than that, PTs are used.