News | company news | Jul 25,2024
Current transformer installation precautions
Things to note when installing current transformers in low-voltage distribution cabinets
1 When the current transformer is running, the secondary side is not allowed to be open.
2 The magnetic potential I1N1 of the current transformer’s primary measured current generates a magnetic flux Φ1 in the iron core;
3. The magnetic potential I2N2 of the current transformer’s secondary measuring instrument generates a magnetic flux Φ2 in the iron core;
4. The combined magnetic flux of the current transformer’s iron core: Φ=Φ1+Φ2;
5. Because Φ1 and Φ2 are in opposite directions and equal in magnitude, they cancel each other out, so Φ=0;
6. If the secondary is open, that is, I2=0, then: Φ=Φ1, the magnetic flux of the current transformer’s iron core is very strong, saturated, the iron core heats up, the insulation is burned out, and the Leakage;
7. If the secondary circuit is open, that is, I2=0, then: Φ=Φ1, Φ generates a very high induced potential e in the secondary coil N2 of the current transformer, forming a high voltage at both ends of the secondary coil of the current transformer, endangering the life safety of the operator;
8. One end of the secondary coil of the current transformer is grounded, which is a protective measure taken to prevent high voltage danger;
Therefore, fuses are not allowed to be connected in the secondary circuit of the current transformer, and it is not allowed to remove the ammeter, relay and other equipment without bypassing during operation.
Current transformer installation precautions

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