Why should the secondary winding of current transformer and voltage transformer be grounded in use
The secondary windings of current transformers and voltage transformers should be grounded during use to prevent the high voltage from being connected to the low voltage through the transformer after the insulation of the transformer is broken down, which will injure the instrument and the user. , which does not affect the normal use of the equipment, but also ensures the safety of personnel and equipment.
In order to ensure safety, the secondary side of the current transformer must be grounded, which plays a protective role when there is a high voltage danger on the secondary side of the current transformer, so as to ensure the safety of people and equipment.
Current Transformer Action
During the production process, the usage status of each primary equipment in the system is monitored to ensure the safe use of the power system. The current transformer usually converts the large current of the primary circuit into a secondary small current proportional to it, and finally outputs the small current of the secondary side to the secondary instrument, relay protection, and automatic device for use. Therefore, the current transformer is the AC current source of electrical control, regulation, measurement and protection components, and also the hub of the connection between the electrical secondary circuit and the primary circuit.
Why can't the secondary side of the current transformer be open? Because the secondary circuit of the current transformer is open, the secondary current disappears, and the demagnetization effect also disappears, which will cause a high magnetic density in the iron core. And because the number of turns of the secondary side winding is much larger than the number of turns of the primary side winding, once the secondary side is open, a very high voltage will appear, sometimes as high as thousands of volts, so not only endanger the secondary side equipment, but also cause serious personal injury. Safety.