Motor energy efficiency testing service

Motor Energy Efficiency Testing Service – Accredited Performance Assessment for Electric Motors in the Brazilian Market

For Brazilian manufacturers, importers, and industrial plant operators, the energy efficiency of electric motors is a critical factor that directly impacts operational costs, environmental sustainability, and regulatory compliance. With rising electricity tariffs and increasingly stringent efficiency regulations – such as INMETRO Ordinance 553/2021, PROCEL (Brazilian National Program for Electricity Conservation), and the ABNT NBR 17094‑1 standard – verifying and certifying the energy performance of electric motors has become an essential requirement for market access and customer satisfaction. Our ISO/IEC 17025 accredited laboratory offers a specialised motor energy efficiency testing service that quantifies the efficiency, power factor, torque, and losses of electric motors across a wide range of power ratings and configurations, using state‑of‑the‑art dynamometers, power analysers, and temperature monitoring systems, in full compliance with IEC 60034‑2‑1, IEEE 112, and the Brazilian standards. With decades of experience in electrical machinery testing and energy efficiency evaluation, we provide precise, repeatable, and fully documented test results that are accepted by INMETRO, PROCEL, and Brazilian certification bodies, supporting your product approval, energy labelling, and sustainability goals.

Motor Types and Products We Regularly Test

We accept a wide range of electric motors, from fractional horsepower motors to large industrial machines, covering all common configurations and technologies. Our test setups are adaptable to different power ratings, voltages, frequencies, and mounting arrangements. Common samples include:

• Single‑phase and three‑phase induction motors – for residential, commercial, and industrial applications.
• Permanent magnet synchronous motors (PMSM) – for high‑efficiency and variable‑speed applications.
• Brushless DC motors (BLDC) – for appliances, automotive, and HVAC systems.
• Servo motors and stepper motors – for precision motion control.
• Motors with variable frequency drives (VFDs) – for evaluating drive‑motor system efficiency.
• High‑voltage motors (up to 13.8 kV) – for heavy industrial and utility applications.
• Motors for compressors, pumps, fans, and conveyors – for process industries.
• Motors with different cooling methods (TEFC, ODP, WPII) – to account for cooling‑related losses.

Core Test Methods – Efficiency, Losses, and Performance Characterisation

Our motor energy efficiency testing service follows the most rigorous and recognised international and Brazilian standards for performance testing. The selection of the method depends on the motor type, power rating, and the specific requirements of the certification scheme:

• Efficiency determination by the input‑output method (loss segregation) – according to IEC 60034‑2‑1, IEEE 112, and ABNT NBR 17094‑1 – We measure the electrical input power (voltage, current, power factor) using a precision power analyser and the mechanical output power using a calibrated dynamometer (torque and speed). We also segregate the losses into five categories: iron losses, copper losses (stator and rotor), stray load losses, friction and windage losses, and additional losses. The efficiency is calculated as the ratio of output power to input power, corrected to a reference temperature of 25°C, 75°C, or 95°C, as specified by the standard. This is the most comprehensive method and is required for efficiency classification according to IE (International Efficiency) codes.
• Efficiency determination by the calorimetric method – for large motors (above 1 MW) where the input‑output method is impractical – We measure the heat dissipated by the motor using a water‑cooled calorimeter, and we calculate the losses from the heat flow. This method is less common but is used for very large machines.
• Loss analysis using the harmonic and stray load loss evaluation (IEEE 112, IEC 60034‑2‑1) – We perform a detailed analysis of the motor’s input current and voltage waveforms to separate the fundamental component from the harmonics. The stray load losses are determined by a separate test (usually by a reverse rotation test or by a locked‑rotor test) and are added to the loss summation.
• Temperature rise test (IEC 60034‑1, NBR 17094‑1) – We operate the motor at its rated load and measure the temperature rise of the windings using the resistance method (or, alternatively, with embedded thermocouples). The temperature rise affects the copper losses, and the efficiency is corrected to the reference temperature.
• Power factor measurement – we measure the displacement power factor (cos φ) and the total power factor (including harmonic distortion) to characterise the motor’s impact on the power grid – This is essential for evaluating the motor’s reactive power consumption and compliance with utility requirements.
• Locked‑rotor and pull‑up torque tests – we measure the starting torque, pull‑up torque, and breakdown torque at rated voltage and frequency, to assess the motor’s ability to accelerate the load – These tests are performed for motor type‑approval and for matching motors to the driven equipment.
• No‑load and short‑circuit tests – we perform these tests to separate the iron losses (from the no‑load test) and the copper losses (from the short‑circuit test) and to derive the motor’s equivalent circuit parameters – These parameters are used for loss segregation and for predicting performance at different operating points.
• Variable speed drive (VSD) efficiency – we test the motor in combination with a VSD to evaluate the overall efficiency of the drive‑motor system, including the harmonic losses and the effect of the VSD on motor heating – This is important for motors that are used with inverters.

Test Set‑up, Instrumentation, and Data Acquisition

Accurate efficiency testing requires precise, high‑quality instrumentation and careful test set‑up to minimise measurement uncertainties and ensure repeatability:

• Dynamometer – we use a high‑precision, water‑brake, eddy‑current, or regenerative dynamometer to apply the mechanical load to the motor, with torque and speed measurement accuracy of < 0.1% – The dynamometer is calibrated with a certified torque transducer and a reference speed encoder.
• Power analyser – we use a precision power analyser (class 0.05) to measure the voltage, current, power, and power factor at the motor input terminals, with sampling rates up to 1 MHz to accurately capture the waveforms and harmonics – The analyser is calibrated with a certified reference power source.
• Temperature sensors – we use type‑T thermocouples, PT100 resistance thermometers, and, for the resistance method, a precise ohmmeter to measure the winding resistance before and after the test – The temperature uncertainty is < 0.2°C.
• Data acquisition system – we use a high‑speed, multi‑channel data acquisition system that records all electrical, mechanical, and thermal parameters simultaneously, ensuring that all measurements are synchronised and traceable – The system is programmed to automatically compute the efficiency and losses.
• Environmental control – the test is performed in a controlled environment (ambient temperature 25°C ± 5°C), with monitoring of barometric pressure and relative humidity, to correct the air density and cooling effects – The test cell is designed to minimise external vibrations and drafts.
• Reference torque and speed calibration – we use a certified reference torque transducer and a reference tachometer to calibrate the dynamometer’s torque and speed measurements before and after each test series – The calibration is traceable to Inmetro.

Efficiency Classification and International Efficiency (IE) Rating

Based on the test results, we classify the motor according to the International Efficiency (IE) rating system, which is adopted in Brazil through PROCEL and ABNT NBR standards. The IE classification is based on the motor’s efficiency at 50%, 75%, and 100% of the rated load:

• IE4 (Premium efficiency) – the highest efficiency level, offering the lowest losses and the best energy savings – Often required for new installations and for motors used in continuous operation.
• IE3 (Premium efficiency) – the baseline for many regulated applications, required by INMETRO for motors from 0.75 kW to 375 kW – Motors must meet IE3 to be sold in Brazil, with certain exceptions.
• IE2 (High efficiency) – an older standard, now largely superseded by IE3 for most applications in Brazil – Still accepted for some repurposed or low‑usage motors.
• IE1 (Standard efficiency) – not allowed for new motors in Brazil (with some exemptions for motors below 0.75 kW or for specific applications) – Motors that fail to meet IE3 or IE4 are not eligible for PROCEL labelling or for sale in the Brazilian market.
• We provide the IE rating and the corresponding efficiency values, along with a compliance statement for the Brazilian regulations – We also supply the detailed loss breakdown, which is required for the technical file in the certification process.

Compliance with Brazilian Standards and Regulatory Requirements

Our motor efficiency testing services directly support compliance with the key Brazilian regulations and standards, ensuring that your motors can be legally marketed and sold in the country:

• INMETRO Ordinance 553/2021 – the main regulation for energy efficiency of electric motors in Brazil – It establishes the minimum efficiency requirements (IE3 for most motor powers) and the test methods (IEC 60034‑2‑1) for motors up to 375 kW. Our tests are performed in strict accordance with this ordinance.
• ABNT NBR 17094‑1 – the Brazilian standard for three‑phase induction motors (performance and tests) – It specifies the efficiency classes, the test procedures, and the tolerances for motors for general use.
• PROCEL Motor Labelling Programme – the voluntary energy efficiency labelling programme that awards the “PROCEL Seal” to motors with the highest efficiency – Our tests provide the data needed for the PROCEL application and the labelling of the motor.
• ABNT NBR IEC 60034‑2‑1 – the Brazilian adoption of the international standard for efficiency testing of rotating electrical machines – Our test methods fully comply with this standard.
• ANP regulations – for motors used in oil and gas applications – Specific requirements may apply for hazardous areas or for motors used in off‑shore platforms.

Reporting and Accreditation

All motor efficiency tests are performed under our ISO/IEC 17025 accredited quality system, with full traceability of all measurement parameters. Our Inmetro‑accredited reports are recognised by INMETRO, PROCEL, ANP, and various Brazilian certification bodies. Each report includes:

• A complete description of the motor (type, power rating, voltage, frequency, frame size, cooling method).
• Test conditions (ambient temperature, barometric pressure, test voltage and frequency).
• Detailed loss breakdown (stator copper, rotor copper, iron, friction and windage, stray load) at each load point.
• Efficiency values at 50%, 75%, and 100% load, corrected to the reference temperature.
• IE classification and comparison with the INMETRO Ordinance requirements.
• Torque‑speed curve (if measured) and power factor data.
• Calibration certificates for the dynamometer, power analyser, and all measurement devices.
• Measurement uncertainty analysis for the efficiency and the losses.
• A clear pass/fail conclusion on the compliance with the regulatory requirements.

Our reports provide the confidence you need to certify your motors, obtain PROCEL labelling, and demonstrate compliance with the Brazilian energy efficiency regulations.

Why Choose Our Motor Energy Efficiency Testing Service?

We understand that energy efficiency is a key driver for industrial competitiveness and environmental sustainability. Our team offers rapid scheduling, flexible test programmes (from single‑point efficiency measurements to comprehensive loss segregation and IE classification), and clear, actionable interpretation of results – we do not just provide a pass/fail; we explain the loss distribution, identify opportunities for efficiency improvement, and help you understand the impact of the drive system on the overall performance. We work closely with your motor designers, plant managers, and procurement teams to select the appropriate test method, load points, and reference temperature for your specific motor type and application. With state‑of‑the‑art dynamometers, precision power analysers, and a highly experienced team, our motor energy efficiency testing service delivers the accuracy, repeatability, and regulatory acceptance you need to ensure your motors meet the Brazilian market requirements and contribute to your energy reduction goals. Contact us to discuss your motor types and efficiency targets – we will develop a customised test programme that provides the definitive evidence of your motor’s energy performance.