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YASKAWA SGMAH-01A1A-SM11 Servo Motor 1000 Nominal Holding Torque 3000 Class F
Item specifics
OTHER SUPERIOR PRODUCTS
SIMILAR PRODUCTS
Computerized Load and Efficiency Estimation Techniques
There are several sophisticated methods for determining motor
efficiency. These fall into three categories: special devices,
software methods, and analytical methods. The special devices
package all or most of the required instrumentation in a portable
box. Software and analytical methods require generic portable
instruments for measuring watts, vars, resistance, volts, amps, and
speed. These need to be instruments of premium accuracy, especially
the wattmeter that must have a broad range including good accuracy
at low power and low power factor.
Washington State University Cooperative Extension Energy Program,
in partnership with the Oregon State University
Motor Systems Resource Facility, recently conducted lab testing of
several efficiency-measuring methods.
These included three special devices: the Vogelsang and Benning
Motor-Check, the ECNZ Vectron Motor Monitor, and the Niagara
Instruments MAS-1000. Their efficiency readings were carefully
compared to “true” efficiency, measured by a dynamometer and
precision lab instruments per IEEE testing standards. From 25% load
to 150% load the special devices tended to hold an accuracy within
3%, even in adverse conditions of voltage deviation and unbalance
on old, damaged, or rewound motors. In less challenging test
conditions, they tended to operate within 2% accuracy. These
instruments require a skilled electrician or other personnel
trained in the safe connection of electrical equipment in
industrial power systems plus about a day of training and practice.
The motors must be temporarily unpowered for a resistance test and
temporarily uncoupled for a no-load test, i.e., running at normal
voltage unloaded. Uncoupling in-situ is rarely convenient, but the
no-load test can be run at times such as receiving inspection or
following service at the shop. No-load performance does not tend to
change significantly over time in the absence of a failure/repair
event.
Software and analytical methods were also tested in the lab
research described above. When measurement of input data was made
with precision lab instruments, the accuracy of methods requiring a
no-load test approached that of the special devices’ performance.
The Oak Ridge National Laboratory has developed ORMEL96 (Oak Ridge
Motor Efficiency and Load, 1996), a software program that uses an
equivalent circuit method to estimate the load and efficiency of an
in-service= motor. Only nameplate data and a measurement of rotor
speed are required to compute both the motor efficiency and load
factor. The program allows the user to enter optional measured
data, such as stator resistance, to improve accuracy of the
efficiency estimate. Future refinements of ORMEL96 are expected to
create a more user-friendly product.
Finally, motor load and efficiency values are automatically
determined when measured values are entered into MotorMaster+
software’s motor inventory module. MotorMaster+ contains a database
of new motor price and performance, and features many motor energy
management capabilities including replacement analysis, maintenance
logging, inventory control, energy and dollar savings tracking, and
life cycle cost analysis. MotorMaster+ is available at no cost to
Motor Challenge Partners.