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### What is the multiplier of the electric meter?

In order to measure the large current, we use a current transformer to reduce the current to the meter, but the current on the meter is reduced. It must be much smaller than the actual current. This is the ratio of the transformer, which is the multiplier of the electric meter.China electronic energy meter suppliers
For example, if the transformer is 400/5, the magnification is 400/5=80. The multiplier of the electric meter generally refers to the product of the transformation ratio of PT (voltage transformer) and CT (current transformer).
The magnification of the electric meter itself, such as 5~10A, is 2 times the meter, 5~40A is 8 times the meter, but this has nothing to do with the meter reading calculation power consumption, it is related to the current transformer magnification. For example, 75/5 means 15 times; 100/5 means 20 times, etc.
Let’s look at an example of an electric meter multiplier:
Multiply the ratio of voltage transformer and current transformer. For example, voltage transformer 10/0.1KV means 10/0.1=100 times. The current transformer 100/5A means 100/5=20 times, 100*20=2000 times, and the meter shows that it is actually 2000 degrees at one time. Low-voltage circuits can be used without voltage transformers.
The principle of current transformer is based on the principle of electromagnetic induction. The current transformer is composed of a closed core and windings.
Its primary winding has very few turns, which is stringed in the line of the current that needs to be measured. Therefore, it often has all the current flowing through the line. The secondary winding has a relatively large number of turns. It is serially connected to the measuring instrument and the protection circuit, and the current mutual inductance When the transformer is working, its secondary circuit is always closed, so the impedance of the series coil of the measuring instrument and the protection circuit is very small, and the working state of the current transformer is close to short circuit.
A current transformer is an instrument that converts a large current on the primary side into a small current on the secondary side based on the principle of electromagnetic induction. The current transformer is composed of a closed core and windings. Its primary winding has a few turns and is stringed in the line of the current that needs to be measured.
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