test transformers are essential in ensuring the optimal performance and reliability of transformers in electrical power systems. It is important to handle the device attentively and abide by all safety protocols. Regular testing of transformers with specialized equipment such as test transformers and AC hi-pot testers helps prevent electrical failures that could result in hazardous conditions, power outages, and system disruptions.
The first step in operating a test transformer is to ensure that it is properly installed and connected to the transformer to be tested. This should be done by a qualified technician in accordance with the manufacturer's instructions and safety guidelines to avoid any potentially hazardous situations.
1. Before the test, check whether the tested object is disconnected from power operation, grounding, and discharge, and whether all external wires are wiped clean. It is strictly prohibited to apply the test voltage to the working part of the person.
2. After the test device is connected, it can be pressurized after review. Special attention should be paid to the safe distance between the high-voltage equipment and the earth, the wire and the operator, and whether the housing of the tested object is reliably grounded. The test shall be conducted in strict accordance with the prescribed specifications.
3, for large-capacity equipment, the oil-immersed test transformer should be slowly increased voltage to prevent the charging current of the measured object from burning out the micro ammeter. If necessary, the transformer should be pressurized step by step to read the stable reading of the microammeter at different voltage levels.
4. Once the transformer is cut off, the cause of a breakdown and flicker of the test device should be identified and recorded in detail.
Connect the working circuit according to your test. Oil-immersed test transformer housing and operating system must be reliably grounded. The X end of the high voltage winding of the test transformer (high voltage tail) and the F end of the measurement winding must be reliably grounded.
5, before switching on the power supply, the regulator of the operating system must be adjusted to zero to switch on the power supply, and the voltage can be increased.
6. During the test, if the measuring instrument indicates that the state of the measured object is abnormal, the voltage should be reduced immediately, the power supply should be cut off, and the situation should be ascertained.
7, after the test, the voltage regulator should return to zero in a few seconds and then cut off the power supply.
8, shall not exceed the rated parameters.