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Specially designed and manufactured for electrical equipment tests in power departments and factories, such as current transformer tests, current load tests, temperature rise tests, and testing the maximum breaking current and breaking capacity of switches. This series of products features a split/integrated structure, with advantages such as infinitely adjustable output current, balanced current rise, wide load variation range, reliable operation, simple operation, and safety. The 2000A high current generator is an ideal equipment for current rise or temperature rise tests in industrial and mining enterprises.
2000A High Current Generator Functional Features
1. This fully automatic 2000A high current generator adopts touch screen control with a full Chinese interface.
2. The 2000A high current generator has a built-in micro printer that can print relevant test data. It has a high degree of automation and is easy to operate.
3. Before the test, parameters such as test current and time can be set as needed.
4. The 2000A high current generator automatically increases the current, and the color large screen displays the output current in real time. After reaching the set current, the timing starts.
5. After the timing is completed, the current is reduced and automatically returns to zero, and the main circuit trips. Turn off the air switch to end the test.
I. Basic Requirements for Temperature Rise Test of 2000A High Current Generator
(1) In order to ensure the accuracy of the temperature rise test data, the accuracy of the meters used to measure the stator electrical quantities should not be lower than 0.5 level, and those for measuring the rotor should not be lower than 0.2 level.
(2) The temperature rise test of the 2000A high current generator generator is a long-term thermal stability test. Each load test requires the rotor current to remain stable, with a variation range not exceeding 1% of the test current; the stator voltage, current, and power should also remain as stable as possible and three-phase balanced, with a variation range not exceeding 3% of the test value. Therefore, during the test, the automatic voltage regulator should be removed, and the power factor should be maintained at the rated value.
(3) During the 2000A high current generator test, the cooling medium temperature should be at or near the rated value. Under each test load, the temperature change of the cooling medium should not exceed 1K.
During the test, under each load, after stabilizing for 1 hour, measure each measured electrical quantity and temperature every 15 or 20 minutes until stability is achieved. The so-called thermal stability means that the temperature of each part of the motor does not change by more than 2K within 1 hour. The time required to reach thermal stability depends on the type and capacity of the motor, generally about 3-4 hours.
II. Preparations Before the Temperature Rise Test of 2000A High Current Generator
(1) Familiarize with Technical Data of 2000A High Current Generator
Before the test, the test personnel should be familiar with the instructions and relevant technical data provided by the electrical equipment manufacturer, especially to clarify the winding insulation structure, insulation level, allowable temperature (temperature rise) limits of each part, operating conditions, and the embedding positions of measuring elements.
(2) Develop Test Plan for 2000A High Current Generator
Based on the mastered situation, jointly discuss and formulate the temperature rise test plan for the 2000A high current generator with relevant technical personnel of the power plant.
(3) Measure DC Resistance of Stator and Rotor Windings of 2000A High Current Generator
When conducting the generator temperature rise test with the 2000A high current generator, the cold-state DC resistance of the generator stator and rotor windings is very important basic data in the temperature rise test. This is because when measuring the average temperature of the stator and rotor windings under power, the cold-state resistance is used as the reference value to convert the average winding temperature, so its measured value directly affects the accuracy of the temperature rise test. Therefore, before the 2000A high current generator test, the DC resistance value should be measured accurately.
The neutral point disconnecting switch of the 2000A high current generator is in the closed position, meaning the transformer neutral point is grounded and operating. At this time, zero-sequence overcurrent protection should be put into operation; when the transformer neutral point disconnecting switch is in the open position, meaning the transformer neutral point is not grounded, zero-sequence overvoltage protection and gap discharge zero-sequence overcurrent protection should be put into operation.
Actual operation shows that this protection has withstood the test in power grids at all levels, without misoperation or refusal. At the same time, this protection method is basically adopted in modern power grid design.
Note: The above information and technical parameters are compiled and published by Yangzhou Dari Electric Co., Ltd.
