A multimeter is a device for measuring voltage, resistance, in some models - capacity. What is a current clamp? This device is necessary to measure current strength, which not every multimeter can. For more details, read further in the article.
Why do you need a current clamp
Clamps allow you to measure the current in a wide range - 100 and even 200 A. On multimeters, the current measurement threshold is at around 10-15 A. If this parameter is higher, then at best the fuse will burn out (if provided constructively), at worst - the device itself.
How to use a clamp meter correctly
The pliers are called so for a reason, these are really 2 semicircular grips, which are spread apart by a small lever, usually located on the side of the device. To measure the current in a conductor, you must follow a simple sequence:
- Press the lever and spread the grippers.
- Close the pliers around the wire to be measured.
- Switch on the device by turning the knob by the measured value (for example, "alternating current").
- The screen will display the value of the current in the wire.
The pliers do not measure the electric current in the conductor itself (then the wire should be broken), but the magnetic field around it. The original clamp meter, also called the Dietze clamp, measured alternating current exclusively. Modern models have a slightly different design device, which allows you to determine several values.
What can be determined with a clamp meter
The first, as mentioned above, is the current strength. And if you know the current and voltage, using a simple formula (P = U * I), you can find out the power consumption of the electrical appliance. Very useful information, for example, when choosing the rating of a circuit breaker.
Also, with the help of such a useful measuring device, you can determine the current leakage, only in this case you should measure the current strength not on the phase wire, but simultaneously on the "phase" and "zero".
Which pliers should you choose?
It is best to opt for a model combined with a multimeter - it is very convenient and there is no need to purchase two digital instruments. But just do not pay attention to cheap Chinese models, which, with frequent use, will not last even a couple of months. A good, high-quality clamp meter cannot cost less than $ 40-60, in principle, like all other electrician's tools.
If you have at your disposal multifunctional tongs and special measuring probes are included in the kit, then with such a device you can practically measure all electrical quantities: AC and DC voltage, resistance, temperature (using a thermocouple) and even "ringing" the wires on integrity.
Advice! In order to always use the pliers, it is better to keep a pair of "AA" batteries or one "Crown" at hand, depending on the model of the device.
Summing up
The current clamp is a must-have tool in the arsenal of any electrician. They may not be needed by home craftsmen, but professionals should always have them at hand.