Transformer (TLMS) & Reactor (RLMS) Loss Measurement Systems

• Single set-up for full voltage and current testing
• Highest available commercial accuracy:
  • Voltage: 0.05 %
  • Current: 0.005 %
  • Power ≤ 0.61 % at PF=0.001
• Helps manufacturers design more energy efficient transformers and reactors
• Power Analyzer-based
• Fast, reliable, accurate measurements
• Wide range of system applications from 1 kV, 1000 A to 300 kV, 6000 A
• Horizontal and vertical bushings
• Standard, Premium, and Yokogawa versions available

Overview

The AccuLoss® Transformer Loss Measurement System (TLMS) and Reactor Loss Measurement Systems (RLMS) from Measurements International Limited are metrology-grade solutions designed for precise transformer and reactor loss measurements. Engineered for modern, high-voltage testing, these systems deliver industry-leading accuracy, even under challenging conditions, like extremely low power factor measurements (PF = 0.001).

Using precision voltage dividers and advanced simultaneous sampling wattmeter technology, TLMS and RLMS provide fast, stable, and highly repeatable results, making them well suited for both production and laboratory environments.

Built on proven metrology principles, the system is simple to calibrate using traceable reference standards. This reduces complexity and downtime while ensuring long-term confidence in measurement accuracy. The modular and scalable architecture supports configurations up to 800 kV and 6000 A, enabling seamless integration into new or existing test facilities across a wide range of applications.

The system supports a comprehensive range of testing applications, including load and no-load loss measurements, heat run testing, induced voltage testing, and reactor calibration at very low power factors. Integrated software provides automated test sequences, waveform analysis, and flexible data output, improving efficiency while maintaining consistent, high-quality results.

Optional oil-filled current transformers (CTs), including electronically aided and compensated designs, further extend system capability-allowing a single platform to support both transformer and reactor testing with high accuracy and stability.

Capabilities and Applications

• Accurate. Defensible. Compliant.
• Single set-up for full voltage and current testing
• Performance of load and no-load loss measurements
• Transformer heat run test
• Induced voltage test
• Zero sequence (Z₀) impedance measurements
• Easy-to-use software includes:
  • voltage and current waveform analysis
  • manual and fully automatic range selection
  • over-voltage
  • over current protection
• Output data: ASCII file for easy import into Excel spreadsheets
• Electromagnetic Compatibility: All components comply with the requirements of IEC recommendations, with the electronics housed in a shielded enclosure

The AccuLoss® System is designed to test small, medium, and large power transformers, up to 400 Hz, ideal for R & D facilities.

The AccuLoss® System also calibrates single- and 3-phase reactors at power factors < 0.001.

Feature

Industry-Leading Measurement Accuracy

• Ensures confidence in results, even at PF = 0.001, supporting compliance with global standards and improving product quality.

Simultaneous Sampling Technology

• Eliminates phase errors and delivers fast, stable, and highly repeatable measurements.

Scalable to 6000 A / 800 kV

• Supports testing from distribution to ultra-high-voltage transformers within a single platform.

Modular System Architecture

• Enables easy upgrades and integration into existing facilities, protecting long-term investment.

Flexible Test Configurations

• Accommodates horizontal and vertical bushings, and a wide range of transformer designs.

Optimized for Low Power Factor

• Maintains high accuracy under the most challenging measurement conditions.

Supports Energy-Efficient Design

• Helps manufacturers reduce transformer losses and meet efficiency requirements.

Environmentally Responsible Design

• Contributes to reduced emissions, and supports ESG and sustainability initiatives.