PPT Slide
Section 13.9: Starting of DC Motors cont.
What’s the motor’s speed if it’s running as shown above (with a 0.1 W resistor placed in the armature circuit)?
From Example 13.7, If = 3.07A., Ia = 42.93A. and k = 0.0668 so the speed equation gives n = (230V. - 0.15W´42.93A.)/(3.07A.´0.0668) = 1090 RPM (Note: P0.1W = (42.93A.)2´0.1 W = 184.3 W.)