Analog Meters -Voltmeters

Learn More About Triplett Analog VOM Meters

What is an AC and DC analog voltmeter?

The DC and AC analog voltmeter is that AC voltmeter that measures the root mean square (RMS) value of the voltage (AC). Against this, the DC voltmeter measures the peak DC voltage. Another key difference lies in its working principle.

• The AC analog voltmeter utilizes a rectifier for signal amplification. The signal thus amplified is converted into DC and is made to pass through the meter comprising a moving coil magnet. This signal varies the pointer indication and then measures the RMS value of voltage – AC.
• The DC analog voltmeter chooses a particular voltage and then attenuates it entirely. It amplifies only the selected voltage and makes it pass through the PMMC meter. It does not use a rectifier for amplifying the signal.

How do you use an analog voltage meter?

Follow the below-given steps to use analog volt meter.

• Take the set of leads or wires in hand. The set comprises red and black wires.
• Connect the black wire to the negative side of the terminal and red to the positive side.
• You can measure continuity using a wire; measure resistance using a resistor; measure AC current and voltage using an AC socket, and measure DC current and voltage using an AA battery.
• Connect DUT and analog voltmeter using the test probes. Check the corresponding reading in the scale.
• Ensure the pointer moves across the scale as per the range chosen.
• Follow the same technique to measure different parameters.

How do you read an analog VOM meter?

You can read an analog VOM meter using the following steps.

• Understand the usage of scales on the analog VOM meter. Typically such devices comprise three scales – Ω scale for resistance reading, AC scale for reading AC voltage, DC scale for reading DC voltage, and so on. There is also a dB scale involved, which is the least used.
• Set the dial for a value higher than the DUT. For instance, if you are testing a 240 VAC water heater, then set the dial to 300 AC. Similarly, set the meter to 150 V if you are testing a regular 120 V outlet.
• Understand the values between the numbers. The analog VOM meters follow the same scale as ordinary rulers. The lines between scales represent the same divisions as on a ruler. If you observe three lines between 50" and 70", perhaps, they may represent 55", 60", and 65".
• Check the settings of the dial and multiply it with the set values. For instance, if the multimeter is set to Rx100 and the needle on measurement points to 50 ohms. Then the value will be calculated as 50 x100=5000 and this will be the actual resistance of this circuit.

What are the applications of an analog multimeter?

An analog multimeter, also known as analog VOM, is widely used across industries. They are most commonly used for oscillation or pulse measurement, as well as battery indicators in naval or marine craft. They are ideal for measuring different parameters in home, commercial and industrial facilities.

What is the function of analog tester?

The analog tester is used to measure various electrical quantities such as current, voltage, resistance, signal power, and frequency. These devices are widely used to identify and rectify problems in electrical circuits.

Can AC voltmeter measure DC?

Yes, AC voltmeter can be used to measure DC. Electrodynamo meter and moving iron type instruments are generally used for measuring the current. Both these instruments offer the RMS value of AC, which equals to the corresponding DC. If a DC current source is connected to the AC voltmeter, then it would give the appropriate reading.

What is the voltage range of analog DC voltmeter?

Analog DC voltmeters are generally available in three ranges - 0-250V, 0-50V, and 0-10V. A user must understand the right display scale before taking the measurements. For instance, if the pointer reads 3V on the 0-10V scale, which is configured for measuring 0-1000V then this reading must be interpreted as 300V.

What is the working principle of analog voltmeter?

The analog tester or voltmeter works on the principle of Ohm’s Law, which highlights the relationship between different electrical parameters. One equation states P=IE, where P stands for power, I for current, and E for voltage. This equation can be easily understood in terms of voltage, resistance, and current. The current is a result of voltage divided by resistance, or resistance is the result of voltage x current.

In an analog tester or voltmeter, the current is passed through a moving coil that lies between two magnets. This moving coil moves along with a permanent magnet on the application of voltage. The voltmeter is connected to the device under test (DUT). The resistor of known value is connected in series to the measurement probes. When the voltage is applied through the coil, a magnetic field is produced, and it produces the pointer deflection. This deflection is directly proportional to the voltage applied to the moving coil. The pointer oscillates for some time, and the reading can be taken when the oscillation stops.  If you are using a DC voltmeter, you will observe the polarity signs on it. The positive side of this voltmeter will be connected to the highest point of potential and the negative to the lowest side to achieve deflection. If you are using an AC voltmeter, you need not worry about the signs of polarity, and can directly connect it. A high voltage voltmeter is produced by connecting it with a resistor.

Contact us to get recommendations for choosing the best analog meter for your applications. Also, have a look at our Digital Multimeter DMM and Clamp-on Meters.