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WR.40A Winding Resistance Tester

The WR.40A is a high-accuracy DC winding resistance tester designed for transformer and inductor resistance measurement. Built with a durable structure and extended data storage, it is suitable for industrial labs, quality control, and field applications. With multiple current ranges, fine resolution, and robust safety features, the WR.40A provides fast, reliable, and precise test results for transformer maintenance and commissioning.

Key Features

  • High-accuracy DC resistance measurement with 0.1μΩ resolution

  • Wide range of test currents (from <20mA up to 40A)

  • Stores up to 1000 groups of test results

  • Rugged design with 15 kg build for industrial use

  • Includes complete accessories for field and lab testing

  • Suitable for transformer winding resistance, inductors, and other DC resistance tests

  • 1-year warranty for reliability and peace of mind

Technical Specifications

Output Current

  • <20mA, 2.5A, 5A, 10A, 20A, 40A

Test Range

  • 50µΩ – 200mΩ (40A)

  • 100μΩ – 1Ω (20A)

  • 500μΩ – 2Ω (10A)

  • 1mΩ – 4Ω (5A)

  • 2mΩ – 8Ω (2.5A)

  • 10Ω – 20kΩ (<20mA)

Accuracy

  • ±(0.2% + 2 readings)

  • ±(0.5% + 2 readings) for 10Ω – 20kΩ

Resolution

  • 0.1μΩ

Data Storage

  • 1000 groups

Working Condition

  • Temperature: 0℃ – 40℃

  • Ambient humidity: ≤90% RH (non-condensing)

Power Supply

  • AC 220V ±10V, 50Hz ±1Hz

  • Fuse: 5A

Max Consumption

  • 1000W

Dimensions

  • Host: 405 × 230 × 355 mm

  • Accessories: 360 × 260 × 180 mm

Weight

  • Host: 15 kg

  • Accessories: 5.5 kg

Test Line

  • Standard: 13 m (customizable length)

Standard Accessories

  • WR.40A Tester – 1

  • 220V power wire – 1

  • Test Lead set (10m) – 1

  • Ground wire – 1

  • Fuse (3A) – 5

  • Instruction manual – 1

  • Factory test report – 1

  • USB-serial wire – 1

  • Accessory case – 1

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