Transformer Turns Ratio Testers | Detailed introduction of technical principles

The core principle of a transformer turns ratio tester is based on the law of electromagnetic induction, employing a voltage method. By applying a known low voltage to one winding, it accurately measures the induced voltage in each winding, thereby calculating the actual turns ratio.

Specifically, the instrument inputs a low-voltage, specific-frequency (usually power frequency) AC signal to one winding of the transformer (e.g., the low-voltage winding). This voltage signal establishes an alternating magnetic flux in the iron core, inducing voltages in all windings. The instrument's high-precision acquisition module synchronously and accurately measures the applied voltage (U1) and the open-circuit induced voltages (U2, U3…) of all other windings under test.

According to transformer principles, under no-load conditions and ignoring minor leakage reactance, the voltage ratio equals the turns ratio (U1/U2 ≈ N1/N2). The instrument, through precise calculation, directly displays the turns ratio (K) and the ratio difference (error %) between each winding. By comparing the measured results with the nameplate standard value or three-phase balance, it can sensitively determine whether defects such as inter-turn short circuits, winding connection errors, or severe deformation exist. Transformer Turns Ratio Tester Range: 0.9～10000

Transformers should undergo regular turns ratio or voltage ratio tests, including semi-finished and finished products during production, transformers before commissioning, and transformers in operation within the power system. Traditional turns ratio bridges are cumbersome to operate, readings are not intuitive, require necessary conversions, and the test results only reflect the turns ratio of one phase. This instrument overcomes the shortcomings of traditional turns ratio bridge tests, completing three-phase turns ratio tests in one operation. It offers fast testing speed, high accuracy, and significantly improved testing efficiency.

240*128 color LCD display for a more intuitive interactive interface.

Wide testing range, up to 10000.

Fast testing speed, single-phase test completed within 5 seconds.

Single-phase/three-phase/Z-type transformer testing.

Features blind turns ratio testing, group testing, and tap position testing functions.

Non-power-off clock and date display.

Non-power-off data storage function (stores up to 200 sets of test data).

High and low voltage reverse connection protection function. Transformer short-circuit and inter-turn short-circuit protection functions.

Miniature thermal printer for printing test data anytime, anywhere; fast and quiet.

Three-dimensional appearance design, novel structure, and good heat dissipation.

Small size and light weight, easy to carry.

Measuring range: 0.9～10000
Accuracy: ① 0.9～500 ±(0.1%±2 digits)
② 500～2000 ±(0.2%±2 digits)
③ 2000～4000 ±(0.3%±2 digits)
④ 4000～10000 ±(0.5%±2 digits)
Resolution: Minimum 0.0001
Output voltage: 160V/10V (auto-switching)
Operating power supply: AC220V±10%, 50Hz (Do not use generator power)
Ambient temperature: -10℃～40℃
Relative humidity: ≤80％RH, non-condensing