A magnetic powder dynamometer uses fine magnetic powder trapped between a rotor and stator to transmit and control braking torque. When an electrical current flows through the coil, the magnetic field causes the powder particles to form chains that resist rotor rotation. Torque is proportional to excitation current and is fully controllable from zero to maximum rated value, including at zero RPM.
EconoTest ECF series covers torque from 2 Nm (ECF2, 80 C, air-cooled) para 2,000 Nm (ECF2000, 15,000 W continuous, water-cooled). The full range includes: 2, 5, 10, 20, 50, 100, 200, 300, 500, 1,000, e 2,000 Nm models. Models below 20 Nm são refrigerados a ar; models of 20 Nm and above are water-cooled.
EconoTest ECF series magnetic powder dynamometers operate at 2,000–5,000 RPM depending on the model. This relatively low speed limit is due to heat generation from powder friction at high speeds. For testing above 5,000 RPM, an eddy current or hysteresis dynamometer is recommended. Magnetic powder dynos are optimized for production line testing and low-to-medium speed applications.
Sim. Like hysteresis dynamometers, magnetic powder dynamometers deliver full rated torque at zero RPM. This makes them suitable for starting torque testing, locked rotor evaluation, and servo/geared motor testing where static load holding and low-speed high-torque measurement are required.
ECF series magnetic powder dynamometers are best suited for: servo motor and servo drive testing, geared motor and gearbox performance validation, wiper motor and small automotive motor testing, starter motor testing (up to medium power), fan and blower motor testing, and production line end-of-line testing where high duty cycle, consistent torque, and fast test cycles are required.
Magnetic powder degrades over time through heat exposure and mechanical stress; the replacement interval depends on duty cycle, operating speed and temperature. High-temperature or high-speed operation accelerates degradation. EconoTest recommends monitoring torque ripple as an indicator of powder condition. Replacement powder and service are available.
EconoTest ECF series achieves torque measurement accuracy of ±0.2% to ±0.5% full scale depending on model configuration. The smooth, stable braking torque characteristic of magnetic powder technology ensures consistent and repeatable measurements across production batch testing scenarios.
ECF2 to ECF10 models (2–10 Nm) are air-cooled and require no external cooling connection. ECF20 and larger models (20 Nm and above) require water cooling. Recommended water flow and pressure specifications are provided with each model. For continuous duty production testing, water cooling is strongly recommended even for lower-torque models to extend powder life.