The Automatic Transformer Ratio Testing Instrument is a high-voltage testing device manufactured in accordance with the "Power Industry Standards of the People's Republic of China," designed under the general technical specification DL/T963-2005. Based on the "Regulations for Handover and Preventive Testing of Power Equipment," it effectively monitors the quality of transformer products during both manufacturing and operation, preventing inter-turn short circuits, open circuits, connection errors, internal faults in voltage regulation switches, or contact failures. It provides accurate data for parallel operation of transformers, making it an ideal instrument for testing transformer ratio sets.

1. Automatic measurement of the transformer's voltage level;
2. Test the ratio and phase angle difference between high voltage and low voltage, and automatically calculate the transformation ratio error and group;
3. Set the parameters once, then you can proceed directly with testing. All data is saved together, allowing for one-time printing.
4. The instrument features various status indicators for high/low voltage reversal and output faults, achieving true intelligence;
5. The instrument features robust internal protection mechanisms that prevent damage in case of output short circuits.
6. The instrument receives a single-phase power supply and automatically generates a three-phase (120°) power supply with adjustable amplitude, stable output, and constant phase.
7. Capable of measuring phase-shifting transformers; rectifier transformers with multiple pulses; Z-type transformers; testing PT and CT.
8. The test output voltage operates at a different frequency, and the results are unaffected by fluctuations in the power supply frequency or amplitude:
9. Six-channel simultaneous sampling enables true three-phase simultaneous measurement;
10. The instrument does not use relays internally, ensuring long-term reliable operation;
11. The instrument is controlled by a microcomputer, equipped with an 800*480 color LCD touchscreen and a high-speed printer, and supports external mouse input for convenient operation.
12. The instrument can automatically store 1,000 data sets internally or save them to an external USB drive.
13. The instrument generates Word reports, facilitating data management and retrieval;
14. The instrument features a wide input voltage range, and it operates normally even when mistakenly connected to AC 380V.

1. Transmission ratio test range: 1–10000
2. Group Test Scope: 1–12
3. Angle test range: 0° to 360°
4. Ratio test accuracy: Ratio range 1–999.9: Class 0.2 Transmission ratio range: 1000–10000:0.5 grade
5. Resolution ratio: 0.0001 0.0001
6. Angle resolution: 0.01° 6. Angle resolution: 0.01°
7. Instrument power input: 220V ±10%,50Hz ±1Hz
8. Operating temperature: -10°C to 40°C; Relative humidity required: <85% RH

4．Panel diagram: