Re: tach stops at 1000 when motor cut off
To explain in more detail:
When no current flows in a meter, the dial pointer returns to the position that represents no current flow. In the case of most meters this usually also corresponds to a zero position on the dial scale. It is also fairly normal that a meter zero position occurs at the extreme of the pointer movement. In the case of a tachometer, neither of these assumptions is true. The zero-RPM scale mark on the tachometer is not coincident with zero current flow. And the zero current flow position is not coincident with the extreme of the pointer movement. The tachometer zero or rest position usually corresponds to about 1,000-RPM on the scale. This is the zero current position. When the meter is operating and indicating below 1,000-RPM the current flow in the meter is actually slightly negative.