When you need to buy and use a current transformer, in fact, like other equipment, you can’t choose casually. Instead, you should choose regular manufacturers and products. Next, you need to pay attention to the current transformer model. There are many people in The experience in this area is relatively lacking, and the equipment I bought is not applicable. The main reason is that the wrong model is selected. In fact, the model of the device will be reflected in the product packaging and body, mainly in the form of letters and numbers.
Description of current transformer model The secondary circuit must be grounded
When the current transformer is working, its secondary side loop 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 a short circuit. The current transformer converts the large current on the primary side into a small current on the secondary side for measurement, and the secondary side cannot be opened.
Because there are still many types and models of current transformers, in order to let everyone choose the equipment they need at a glance, letters and numbers are usually used to indicate the current transformer model. Can you understand it?
It can be seen from the second letter, which represents the installation method of the current transformer, the third letter represents the insulating medium, the fourth letter is mainly related to the protection level, and the last one is a number, which represents the voltage level and The serial number of the product.
About the grounding of the secondary circuit of the current transformer:
The current transformer model can fully meet the needs of people at this stage, but it is not enough to buy the right one. Next, it needs to be installed and used correctly. One of the precautions is the grounding problem of the secondary circuit.
That is to say, the secondary circuit of the equipment must be grounded. This is also a measure to ensure safety because if the insulation between the primary and the secondary is destroyed, the high voltage in the primary circuit will enter the secondary, which It will cause damage to the equipment, and it will also affect the lives of people around, so it must be grounded, and only one point can be grounded.