It is a strong argument for measuring your own motor constants. This means that using nominal values or inaccurate values will yield less than desirable simulation results. More accurate the simulations will be for any given motor. Obviously, the more accurately the constants are measured, the Using these 3 constants, the performance of any electric motor can be predicted fairly accurately with simulation software.
And the motor winding resistance (Rm), also abbreviated Ri The three motor constants which are very handy to know about any electric motor are:ģ. (who is well known and trusted for their IC engines), brought out their first electric outrunners, the specs for the OMA-3825-750 motor were horribly incorrect.
#Motor winding resistance values how to
Some manufacturers don't even bother to give the basic specs, presumably because they don't know how to determine the motor constants.Īnd sometimes manufacturers make mistakes. In some extreme cases, manufacturers even publish inflated Kv values, hoping to take advantage of the notion that bigger is better. Therefore, a manufacturer may round the Kv value to the nearest 50 or 100 according to what they measured on a test sample. On commercial motors, the stated Kv is usually a nominal value, because no two electric motors are completely identical. Once you know how to measure Kv, you'd want to do it whenever you buy or rewind a motor, to confirm the Kv value. All that is required is a way to measure volts accurately (multimeter), a tacho to measure RPM and a drill press or another method to spin the motor at a constant speed. Have you ever wondered if it's possible to measure the Kv of an electric motor yourself? The answer is "yes", and it is actually quite easy to do at home with relatively inexpensive equipment that you may already have.