Learn about clamp meters in 1 minute
Various inspection instruments and equipment need to be applied in the elevator maintenance process, such as clamp meter, temperature and humidity meter, insulation resistance tester, push-pull force meter, tachometer, vernier caliper, magnifying glass, steel tape measure, steel ruler, magnetic force line Hammer feeler gauge, timer, common electrical tools, etc. Among them, clamp meter is one of the most frequently used inspection instruments.
The clamp meter is a portable instrument that can directly measure the AC and DC current of the circuit without disconnecting the circuit. It is easy to use and widely used in electrical maintenance. For example, a clamp ammeter can be used to measure the working current of a running AC motor, so that it is very convenient to know its working condition when it is under load.
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So, what is a clamp meter? What does it have to do with circuit testing, what can we use it for, how does it run and "work"...As one of the commonly used instruments in the electrical testing industry, how does it ensure the safety of staff and electrical equipment? How to play an indispensable role in daily maintenance?
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What is a clamp meter
The clamp meter is a portable instrument that can directly measure the AC and DC current of the circuit without disconnecting the circuit. It is easy to use and widely used in electrical maintenance. Like the multimeter, the clamp meter has also gone through the process from analog to digital, and it is more convenient and quicker than the multimeter when detecting current. Due to the built-in current transformer in the instrument, the digital clamp meter has very rich functions. It can measure AC and DC voltage, current, capacitance, continuity, diode, resistance, temperature, frequency and other parameters without disconnection.
Difference Between Clamp Meter and Multimeter
To test the voltage and frequency of the multimeter, the multimeter must be connected to both ends of the target to be tested. To test the current, the line to be tested needs to be disconnected for testing. It is not very convenient for most on-site testing. It is generally used to test small currents. The clamp meter is ready to use, and different sizes of jaws correspond to different sizes of wires.
How Clamp Meters Work
A clamp meter essentially consists of a current transformer, a clamp wrench and an ammeter. The iron core of the current transformer can be opened when the wrench is squeezed tightly, and the wire through which the measured current passes can pass through the opening of the iron core, and the iron core is closed when the wrench is released. The measured circuit wire passing through the iron core becomes the primary coil of the current transformer, and the current is induced in the secondary coil through the current, and the ammeter connected to the secondary coil will display. The clamp meter uses the principle of AC electromagnetic induction, which can measure a much larger current than the multimeter, real-time measurement, real-time reading, no need to disconnect, convenient and fast.
