Learners examine the circuitry in a DC variable speed drive that prevents the motor from running at 0 rpm or at maximum speed under certain conditions.
Learners read an explanation of the RL time constant and examine the formula for calculating the instantaneous current value. The current is graphed as it climbs to maximum or drops to zero. Note* In the formulas in this module, the Greek letter epsilon should be the mathematical constant 'e'.
Learners examine the use of the tolerances displayed in a title block by calculating the minimum and maximum allowable size of a fabricated part. In a brief quiz, students determine whether a part is usable or should be scrapped.