In the clear rules of the electrical safety work regulations, the secondary line side of the current transformer must be firmly grounded. The intention is to prevent the primary side insulation from carrying high voltage into the secondary side, which would damage the appearance of the person and the secondary side. Therefore, the secondary line side of the current transformer must be firmly grounded.
When the current transformer has a second open circuit fault, the correct and safe treatment method is: power off the high-voltage side and process it (recover the open point to the normal circuit state), but this will form an unplanned power outage; an unconventional treatment method Yes: As the current transformer is open, there is a discharge phenomenon at the open circuit point, which is relatively simple to find. A wire can be used (the wire diameter should meet the rated secondary current requirements of the current transformer. Generally, the rated secondary current of the current transformer is 1A or 5A, and the use of a 2 square wire is fine), first connect one end of the wire to the open coil The grounding terminal is well connected, and use an insulated tool to connect the other end of the wire to the remote fixed connection point of the open point to achieve the intention of shorting the open point.At this time, the open point can be handled relatively easily to avoid power outages. This method should not be initiated from a safety point of view, but in order to avoid the occurrence of assessment incidents, it can be done by experienced secondary system operators.
Precautions for open circuit of current transformer secondary circuit:
1. The current transformer-secondary circuit does not allow the installation of short-circuit protection devices such as fuses;
2. The secondary circuit of the current transformer is generally not switched. When it is necessary to switch, there should be reliable measures to avoid open circuits;
3. Relay protection and measurement appearance-generally unsuitable current transformer When it is necessary to use it together, the measurement appearance should be accessed through the intermediate converter;
4. It is necessary to short-circuit and ground the terminals of the secondary winding of the installed current transformer without using it;
5. The terminals of the secondary circuit of the current transformer should use the experimental terminals;
6. It should be ensured that the connecting wires of the secondary circuit of the current transformer have sufficient mechanical strength.https://www.ctsensorducer.com/