Why is important to have the meter set in the correct range?

It is important to ensure that the negative lead is in the negative or common connection. Set the meter range to accommodate the largest expected value and allow a little extra as damage could result from high voltages or voltage reversal.

How does the voltmeters resistance affect measurements?

Now, the voltmeter can only indicate the voltage its connected across. The very act of connecting the voltmeter to the circuit makes it part of the circuit, and the voltmeter’s own resistance alters the resistance ratio of the voltage divider circuit, consequently affecting the voltage being measured.

Why do voltmeters have a high resistance?

A voltmeter measures the difference in voltage between the two different points (say, on opposite sides of a resistor), but it does not adjust the amount of current passing between these two points through the device. It will therefore have very high resistance, so that it does not draw current through it.

Why do we have to be sure in setting the correct range setting of the multi tester when doing measurement?

With the multimeter connected, we can now set the dial to the proper setting and measure some current. Measuring current works the same as voltage and resistance — you have to get the correct range.

How different current range can be achieved?

It is possible to extend the range of an ammeter by using a shunt. This shunt provides a bypath for extra current because it is connected across (i.e. in parallel with) the instrument. These shunted instruments can be used to measure currents many times greater than their normal full-scale deflection currents.

Can a voltmeter measure more than one voltage range?

Reading a voltmeter designed to measure only one voltage range is simple and straightforward, but many meters are configurable to measure multiple ranges and therefore employ more complicated scales. Many analog multimeters can measure both AC and DC voltages and can measure dozens of voltage ranges.

How do you extend the range of a voltmeter?

Range Extension of Voltmeters. Multipliers are used for the range extension of voltmeters. The multiplier is a non-inductive high-value resistance connected in series with the instrument whose range is to be extended. The combination is connected across the circuit whose voltage is to be measured.

How to increase the range of PMMC voltmeter?

The range of the PMMC voltmeter increases by connecting the resistance in series with it. The MI instrument means moving iron instrument. This instrument uses for the measurement of both the AC and DC voltage.

What is the resistance of a moving coil voltmeter?

The combination is connected across the circuit whose voltage is to be measured. Example: A moving coil voltmeter reading up to 20 mV has a resistance of 2 ohms. How this instrument can be adopted to read voltage up to 300 volts. Shunts can not be used to extend the range of moving-iron AC ammeters accurately.