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On-load tap changer tester operation

time:2021/10/15   source:华天电力  reading:249 time

Related instructions:


1. In the actual measurement, the measured waveform is often worse than the theoretical waveform, especially when there is a winding measurement. This is because the oscillation signal caused by the inductance and capacitance parameters of the transformer winding during the measurement, and the mechanical vibration of the tap switch, make the The measured waveform shows some fluctuations, which cannot be avoided in the actual test. Some new switches exhibit insulation under low voltage due to the protective oil film on the switch contact points; and switches with longer service life and oxidation of the switch contact points. The waveform may be possible during the test, which is also a normal phenomenon. You can switch several times on this gear to make the oxide layer thinner and increase the contact area, and then use the instrument to test, which may avoid this phenomenon.


2. Another phenomenon is the over-range test. For example, when the transition resistance of the test switch is greater than 9Ω, and the measurement is performed when the range is 9Ω, the result will appear as the waveform shown in Figure 21. At this time, the transition resistance indicated by cursor 1 may be normal, and the transition resistance indicated by cursor 2 is displayed as 50.0Ω. This is due to the over-range. Just change the range to 30Ω and perform the test. It is also possible that in the middle of the transition process, the flat and straight lines are both 50.0Ω, which is also the result of over-range, so you only need to change the range to 30Ω.


Matters needing attention during operation:


1. The instrument can be measured with a coil, but it is strictly forbidden to measure with electricity, and disconnect the connection of the test terminal;


2. When testing with windings, the non-test terminal of the transformer should be three-phase short-circuited and grounded, and the O terminal of the instrument should not be grounded;


3. For the on-load switch that has not been moved for a long time, the switch should be changed many times before the test to remove the oxide layer on the contact surface and the impurities between the contacts;


4. Before use, the ground terminal of the instrument must be connected to the ground wire;


5. It is not possible to connect more than two sets of wires together as one measurement, and the unused wires should be opened;


6. During the test, the test wire is not allowed to be removed;


7. After the test is over, turn off the instrument before removing all wiring.


Performance characteristics:


1. It can realize the measurement of parameters such as transition waveform and transition time, transition resistance, and three-phase consistency.


2. Screen dot matrix LCD display, hierarchical Chinese menu, easy and quick operation.


3. Intelligent test and result analysis, enlarge or reduce the waveform test result.


4. Three independent constant current sources are suitable for measurement without windings, and three independent constant current sources are suitable for measurements with and without windings.


5. Six independent signal processing, high-speed A/D conversion, 10KHz high-speed sampling, reflecting the change of parameters.


6. The built-in uninterruptible power storage can save three sets of waveforms and data, which can be archived, read, and analyzed.


7. Comes with a perpetual calendar, displays the date and time, and can be automatically printed.


8. The instrument is equipped with a high-speed printer, which can print test results.


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Wiring of Microcomputer Relay Protection Tester  | 2021/10/15 | reading253time Safe operation of on-load tap-changer tester  | 2021/10/14 | reading254time return