Tips for purchasing a clamp meter
1: Detection object
Select the model according to different detection objects, AC current, DC current, or leakage current;
2: Detectable conductor specifications
Depending on the testing location, there are different specifications from 21mm diameter to 53mm diameter.
3: Is true value detection necessary?
A clamp-on ammeter using the average value method cannot correctly detect non-sinusoidal circuits such as motors and transformer circuits. A true-rms method clamp-on ammeter should be used to detect such circuits.
4:Other functions
Not only can it detect current, but it also has a model that integrates detection function and recording output.
Clamp ammeter is referred to as clamp meter. Its working part mainly consists of an electromagnetic ammeter and a through-core current transformer. The iron core of the feed-through current transformer is made into a movable opening and is in the shape of a clamp, hence the name clamp ammeter. It is a portable instrument that can directly measure the AC current of a circuit without disconnecting the circuit. It is very convenient to use in electrical maintenance and is widely used.
Clamp meter (clmp ampere meter), also known as clamp meter, is an instrument that integrates current transformer and ammeter. It is an important branch of digital multimeter; it is a portable instrument that can directly measure the AC current of the circuit without disconnecting the circuit. type instrument. Here's how to use a clamp meter correctly:
1. First, correctly select the voltage level of the clamp-type ammeter, check whether its insulation is good, whether it is damaged, whether the pointer swings flexibly, and whether the jaws are rusted, etc. Estimate the rated current based on the motor power to select the range of the meter.
2. Before using the clamp ammeter, you should read the instruction manual carefully to find out whether it is an AC or AC-DC dual-purpose clamp meter.
3. Since the accuracy of the clamp ammeter itself is low, when measuring small currents, the following method can be used: first wind the wire of the circuit under test several times, and then put it into the jaws of the clamp meter for measurement. At this time, the current value indicated by the clamp meter is not the actual value being measured. The actual current should be the reading of the clamp meter divided by the number of turns of the wire.
4. The jaws of the clamp meter should be closed tightly during measurement. If there is noise after closing, you can open the jaws and reset it once. If the noise still cannot be eliminated, check whether the joint surfaces on the magnetic circuit are smooth and clean. If there is dust, Wipe clean.
5. The clamp meter can only measure the current of one phase conductor at a time. The conductor to be measured should be placed in the center of the clamp window. Multi-phase conductors cannot be clamped into the window for measurement.
