7 Ways to Use a Digital Clamp Meter
Clamp meter (sometimes called clamp meter, clamp meter) AC / DC clamp meter is also used as one of the necessary test tools in the daily maintenance work, mainly used for testing the voltage, current, frequency and other related parameters, which requires it to have a high test resolution, test accuracy and more test functions. Clamp meter working principle Clamp ammeter is a combination of current transformer and ammeter. The core of the current transformer can be opened when the spanner is pinched; the current to be measured through the wire can not be cut off through the core of the open gap, when the release of the wrench after the core is closed. Through the core of the measured circuit wire becomes the primary coil of the current transformer, which passes through the current will be induced in the secondary coil current. Thus, the secondary coil connected to the ammeter will have an indication ----- of the current of the line under test. Clamp meter can be through the switch gear, change different ranges. However, it is not allowed to operate with electricity when switching gears. Clamp meter general accuracy is not high, usually 2.5 ~ 5 level. In order to facilitate the use of the table, there are different ranges of switch for measuring different levels of current and voltage measurement function.
Clamp meter selection
1, in the use of the manual should be carefully read before, to find out whether the AC or AC and DC dual-use.
2, the measured circuit voltage can not exceed the value indicated on the clamp meter, otherwise it is easy to cause grounding accidents, or cause the risk of electric shock.
3, each time you can only measure the current of a phase of the conductor, the measured conductor should be placed in the centre of the clamp window, not the multi-phase conductor are clamped into the window measurement.
4, clamp meter measurement should be estimated before the size of the measured current, and then decide which range. If you can not estimate, you can first use the maximum range file and then change the appropriate smaller, in order to read accurately. Can not use a small current file to measure large currents. To prevent damage to the instrument.
5, the jaws in the measurement should be closed tightly, after the closure, such as murmurs, you can open the jaws to reclosed once, if the murmurs can not be eliminated, you should check the magnetic circuit of the joint surface is clean, there is dust and dirt should be wiped clean.
6, due to the clamp ammeter itself is less accurate, in the measurement of small currents, the following method can be used: the first will be measured circuit of the wire around a few turns, and then put into the jaws of the clamp meter for measurement. At this point, the current value indicated by the clamp meter is not the actual value of the measurement, the actual current should be the clamp meter reading divided by the number of turns of the wire winding.
7, maintenance, do not operate with electricity to prevent electric shock. Clamp meter use and precautions Clamp ammeter sub-high and low-voltage two kinds, used in the case of not dismantling the line to directly measure the current in the line.
