Engineers and electricians use two meters to measure current, voltage, resistance, capacitance, etc. One is a clamp meter, a current measuring instrument having some of the qualities of a voltage measuring device. The second one is a multimeter, mainly used for the measurement of voltage, but also has current measuring abilities.
This article attempts to explain the differences between clamp meters and multimeters. We will compare the appearance, measurements, accuracy, and safety of multimeters and clamp meters.
Using clamp meters, electricians can avoid the traditional method of breaking a circuit and then connecting a meter in series within the circuit to take out current measurements. One can measure current by placing a conductor in the jaws of a clamp meter. It is not necessary for a clamp meter's jaws to touch the current-carrying conductor in order to take successful measurements.
With a clamp meter, AC current measurements can be made without contact. The flow of current through a wire involves forming a magnetic field that causes a Hall Effect sensor to calculate the current.
Digital multimeters are often employed by technicians in the electrical/electronic industry. The voltmeter measures voltage between two points, the ohmmeter determines resistance, and the ammeter measures current passing through the conductor.
These types of meters use probes to measure current, voltage and resistance. Unlike clamp meters, multimeters have to be connected to a circuit using parallel and series connections to measure voltage and current respectively.
- Voltage measurement of direct current and alternating current.
- The measurement of direct and alternating currents.
- Resistance, electric Capacitance, and inductance measurement.
Clamp Meter Vs. Multimeter – Appearance
The Appearance of a Clamp Meter
The structure of clamp meters is straight forward; they're non-contact test tools that clamp around a cable and measure amperage inductively. This no-contact test tool is usually called clamps or jaws.
A clamp meter has a display that shows measurements to the user. Most clamp meters also feature ports for connecting probes to accommodate the different measurements, which allows the clamp meter to perform many of the same functions as a multimeter.
The Appearance of a Multimeter
This type of meter displays a dial and a display and is either auto or manual-ranging. Multimeters are mostly digital nowadays, available in various models by various companies.
Multimeters have a selector knob, through which a user can select resistance, current, and voltage measurements. Advanced meters can also measure frequency, capacitance, transistor tests, and more. Most multimeters have different probe ports for measuring Volts and Amps.
Clamp Meter Vs. Multimeter – Measurement:
Clamp Meter is for Current Measurement
We know that the magnetic field occurs within a conductor when current flows through it. Using this phenomenon, we can measure current efficiently, conveniently, and safely operating a clamp meter without test leads. Using this device, the magnetic field can be detected to give a reading of the corresponding current. That's why the clamp meter is considered best for current measurement.
Modern clamp meters have the feature of measuring other parameters, but the primary function of the clamp meter is to measure the current passing through the conductor.
Multimeters are for Multipurpose Measurements
By using multimeters one can measure multiple electrical parameters, such as:
- AC & DC voltages.
- AC & DC current.
- Multimeters can also measure resistance.
- Frequency (If you have a frequency, you can also have a Time Period)
- Several multimeters allow you to measure temperature, but you need to connect a thermocouple for this purpose.
Clamp Meter Vs. Multimeter – Accuracy
Accuracy of a Clamp Meter
These meters are usually pretty accurate with AC and DC measurements within 2%. Specialty models can be as accurate as 0.5%. The vast majority of clamp meters can measure up to 600A AC.
Accuracy of a Multimeter
The accuracy of standard analog multimeters is typically 3%, but instruments of higher accuracy exist. A typical digital multimeter's accuracy is 0.50% for DC voltage ranges.
Clamp Meter Vs. Multimeter – Usage Safety
Clamp meters have gained popularity because of their usage safety because technicians can use them without disconnecting or cutting into power wires. The transformers of these meters do not require contact with a conductor.
The best thing about clamp meters is that it is not mandatory to turn off the current carrying circuit in a measurement.
A multimeter is commonly used for voltage testing; holding the probes so close to two points in a high-voltage circuit can be dangerous. To test the current, a multimeter is connected in series within the circuit requiring the circuit to be disconnected first. It's time-consuming and potentially problematic.
So, compared to clamp meters, these meters are less safer for technicians or engineers. For measuring current nothing beats the clamp meter.