During the production of semi-finished and finished power transformers—as well as prior to the commissioning of newly installed transformers and in accordance with the preventive testing regulations of the national power authorities—it is mandatory to perform turns ratio or voltage ratio tests on transformers. Traditional ratio bridges suffer from cumbersome operation, non-intuitive readings, and the necessity for manual calculations; furthermore, testing can only be conducted on a single phase at a time, resulting in low work efficiency. This series of instruments overcomes the shortcomings associated with traditional ratio bridge testing. Featuring a large-screen color LCD with English menu prompts, the device offers simple and intuitive operation. It completes three-phase ratio testing in a single sequence, delivering high testing speed, superior accuracy, and comprehensive protection functions. This instrument series offers two power supply modes—external AC 220V and internal battery—providing users with maximum convenience during testing.

Key Features

1) The user interface utilizes an intelligent color screen display, ensuring simple and convenient operation.

2) Fast testing speed: Three-phase ratio testing can be completed with a single set of connections in just 10 seconds.

3) Features a "blind testing" function, allowing for ratio and vector group testing even when the high-voltage and low-voltage winding connection methods are unknown.

4) Suitable for ratio, vector group, and polarity testing on a wide range of equipment, including distribution transformers, transformers up to 1000kV, single-phase transformers, current transformers (CTs), voltage transformers (PTs), and Z-connected transformers.

5) Wide testing range: Ratios of up to 10,000 can be measured, and up to 197 tap positions can be tested.

6) Dual AC/DC capability: Supports adaptive power supply via internal lithium battery or external 220V AC charger.

7) Features a non-volatile real-time clock and date display. Data storage options include both internal memory and USB flash drive storage; the internal memory can store up to 500 test records, which can then be transferred to a USB drive. Data stored on the USB drive is saved in Word format, allowing for direct editing and printing on a computer.

8) Equipped with comprehensive protection functions, including protection against reverse connections (high/low voltage terminals) and protection against transformer short circuits or inter-turn short circuits.

9) Compact size and lightweight design ensure easy portability and convenient field use. Technical Specifications

1) Measurement Range: 0.9 – 10,000

2) Accuracy: ±(0.2% of reading + 2 digits) (for values ≤ 500)

±(0.5% of reading + 2 digits) (for values > 500)

3) Resolution: 0.9 – 9.9999 (0.0001)

4) Power Supply: Built-in battery or external charger; Charger specifications: Input 100–240 VAC, 50/60 Hz

5) Charging Time: Approx. 5 hours

6) Instrument Weight: 3.8 kg

7) Instrument Dimensions: 380 mm (L) × 310 mm (W) × 150 mm (H)

8) Operating Temperature: -10°C – 50°C

9) Relative Humidity: < 90% (non-condensing)