Working Principle of Voltmeter

RT wrote:What is the essence of understanding this principle?

It is helpful because we learn how the voltmeter works.

RT wrote:Does the DC and AC voltmeter has a same principle?

A DC voltmeter also has polarity signs on it; therefore one has to connect the plus (+) terminal of the voltmeter to the higher point of potential and the minus (-) terminal to the lower point of potential in order to obtain an upscale meter deflection.

An AC voltmeter does not have any polarity signs on it, but the instrument is still connected in parallel to the component for which the voltage is desired. As a voltage measurement does not involve breaking the circuit, the voltmeter needs to be connected only when a reading is desired.

nicah wrote:Why we need to study the principle of volt meter?

We need to know the working principle of a voltmeter to learn how it works and to appreciate it.

We need to study the principle of voltmeter for us to identify and to know right usage of this meter

But, what is the proper usage of voltmeter?

What is the importance of principle of voltmeter?

Why the title says VOM when all the sub topics only focuses on the voltmeter only?

We do really need to know how to use voltmeter. How about the VOM?

Guide on how to use a multimeter to test for Resistance
Resistance testing is done to ensure the load or circuit being tested is complete. A complete circuit means there is no break or opening in the wires connected to the load or the internal components of the device being tested. An open circuit or broken line means that the load will not work as designed. Resistance testing is sometimes referred to as continuity testing. Continuity testing does the same action as resistance testing with the exception that continuity testing emits an audible sound indicating that the circuit or wires are complete. The resistance testing and continuity testing are also a good way to check for short-circuits and the ground fault which are events that cause circuit breakers to trip, fuses to blow, and possible injury to workers in the field.

MasterJake wrote:What is the difference between AC and DC?

AC is alternating current while the DC is direct current

Julie Angala wrote:We do really need to know how to use voltmeter. How about the VOM?

VOM is combination of voltmeter, ohmmeter and milli ammeter.. in terms of scale and ranges becuase it is not the volts only

Julie Angala wrote:Why the title says VOM when all the sub topics only focuses on the voltmeter only?

for me no, becuase VOM is not only focuses on volts. it can also measure the resistance and the current

Peter Shaquelle Daling wrote:But, what is the proper usage of voltmeter?

voltmeter is only for measuring the voltage... here are the steps.

-Plug your black and red probes into the appropriate sockets (also referred to as "ports") on your multimeter. For most multimeters, the black probe should be plugged into the socket labeled "COM," and the red probe into the socket labeled with a "V" (it might also have some other symbols). Remember to check out our image gallery, the Multimeter Overview tab, or your multimeter's manual if you have trouble identifying the right socket.
-Choose the appropriate voltage setting on your multimeter's dial. Remember that most battery-powered circuits will have direct current, but the setting you select will depend on the science project you are doing. If you are working with a manual-ranging multimeter, you can estimate the range you need based on the battery (or batteries) powering your circuit. For example, if your circuit is powered by a single 9V battery, it probably doesn't make sense to select the setting for 200V, and 2V would be too low. If available, you would want to select 20V.
-Touch the probe tips to your circuit in parallel with the element you want to measure voltage across (refer to the Multimeter Overview tab for an explanation of series and parallel circuits). For example, Figure 6 shows how to measure the voltage drop across a lightbulb powered by the battery. Be sure to use the red probe on the side connected to the positive battery terminal, and the black probe on the side connected to the negative battery terminal (nothing will be harmed if you get this backwards, but your voltage reading will be negative).

How does a voltmeter actuallywork?

What is the sign of a voltmeter not working?

Why is AC considered more efficient than DC?