If measuring a DC current, don't forget to perform zero-adjustment. Position the wire in the center of the clamp for maximum measurement accuracy. Clamp meters designed to measure load currents can only be clamped around one wire.
Be careful not to clamp the instrument around multiple wires at the same time as doing so will prevent proper measurement. Clamp meters designed to measure leakage currents require a bit more caution.
Ground wires should be measured alone. If measuring an AC circuit, clamp the instrument around all the wires two if single-phase; three if three-phase. By using a clamp meter, the minute difference flowing in both directions can be detected and identified as leakage current. As with analog multimeters and digital multimeters, there are a number of precautions that should be borne in mind when using a clamp meter.
For example, if you leave a clamp-on power meter connected after use, an excessively large current flowing to the clamp sensor could damage the instrument. Additionally, avoid clamping an instrument to a bare conductor; clamp meters should only be used to measure insulated conductors although this depends on the specific current sensor in use.
Finally, the instrument's barrier indicates the safety limit, so never touch anything on the jaw side of the barrier while using the instrument. Choose an AC load current clamp meter for ordinary measurement applications, or a leakage current clamp meter if you need to measure leakage currents caused by insulation defects or current flowing in a ground wire for electrical equipment. However, these instruments can be dangerous if used improperly. Americas English.
Ready to learn? What is a clamp meter? Broadly speaking, there are two types of clamp meter: Models designed to measure load current Models designed to measure leakage current Instruments can be further classified based on other differences, for example whether they measure direct current DC or alternating current AC , and whether they use mean value rectification or the RMS method.
Position of the wire is in the center of the clamp recommended. Position of the wire is out of the center of the clamp discouraged. The flow of current through a wire involves forming a magnetic field that causes a Hall Effect sensor to calculate the current. 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.
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. 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. 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.
Specialty models can be as accurate as 0. The vast majority of clamp meters can measure up to A AC. A typical digital multimeter's accuracy is 0. 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.
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