The KDB-II fully automatic transformer ratio group tester is used to monitor the quality of transformer products during factory delivery and use, preventing inter turn short circuits, open circuits, connection errors, internal faults or contact faults of voltage regulating switches. Providing accurate data for parallel operation of transformers is a routine equipment for testing transformer ratio groups.


The KDB-II fully automatic variable ratio group tester has a small size, light weight, high accuracy, and good stability. It adopts a large screen English display, menu operation, and user-friendly interface. The variable ratio group can be tested in one go.

1. Automatically measure the gear of the transformer;

2. Test the ratio and phase angle difference of high voltage to low voltage, automatically calculate the transformation ratio error and group;

3. Parameter setting once, can be tested directly afterwards, data saved together, and printing can be completed in one go;

4. The instrument has various status prompts such as high and low voltage reversal, output faults, etc., achieving true intelligence;

5. The instrument has powerful protection functions inside, and the output short circuit does not damage the instrument;

6. The instrument inputs a single-phase power supply and automatically generates a three-phase (120 °) power supply with adjustable amplitude, stability, and constant phase;

7. Capable of measuring phase-shifting transformers and rectifier transformers with multiple pulses Z-type transformer. Testing PT. CT;

8. The test output voltage is out of frequency, and the results are not affected by fluctuations in the frequency and amplitude of the power supply

9. Six channel simultaneous sampling to achieve simultaneous measurement of three phases;

10. There is no relay used inside the instrument, and it can operate normally for a long time;

11. The instrument is controlled by a microcomputer, equipped with an 800 × 480 color LCD touch screen, high-speed printer, and supports external mouse for easy operation;

12. The instrument can automatically save 1000 sets of data internally, or it can be saved externally with a USB flash drive;

13. The instrument can generate Word reports for easy data management and retrieval;

14. The input voltage range of the instrument is wide, and the AC380V instrument is working normally due to misconnection.

1. Variable ratio test range: 1-10000
2. Group testing scope: 1-12
3. Angle testing range: 0 °~360 °
4. Accuracy of ratio testing: Ratio range 1 to 999.9: Level 0.2; Variable ratio range 1000-10000: Level 0.5
5. Variable ratio resolution: 0.0001
6. Angle resolution: 0.01 °
7. Instrument power input: 220V ± 10%, 50Hz ± 1Hz
8. Operating temperature: -10~40 ℃ Operating relative humidity:<85% RH