General Tools and Instruments CT6235B - Manual (Page 11)

Cradle the tachometer in your right hand. While pressing the
Measurement button on the right side of the instrument with
your right thumb, gently push the cone-tipped end of the rpm
adapter into the cavity at the end of the spinning motor or
generator shaft whose speed you wish to measure. Take care
to keep the two shafts aligned. When the displayed reading
has stabilized, and while keeping the Measurement button
depressed with your right thumb, press the MEM button on
the front panel with your left thumb to store the measure-
ment. Make and store as many measurements as you wish,
using the lessons learned during the simulation exercise.
If the end of the shaft whose speed you want to measure is
flat or slightly convex and has a diameter of 0.25 in, locate
the rubber fitting with a 1/4 in. diameter hole at its wider end.
Insert the narrow end of this fitting into the black plastic
sleeve on the instrument’s shaft. Make sure the function
switch is set to “rpm”. Then, while cradling the tachometer
in your right hand, carefully push the other end of the fitting
around the end of the motor or generator shaft. Take care to
line up the shafts of the equipment and the tachometer. Using
the Measurement and MEM buttons, make and store as
many readings of rotational speed as you wish.
MEASURING LINEAR SPEEDS
To measure the linear speed of a conveyor belt, remove
the plastic sleeve and any rubber fitting inserted in it from
the tachometer’s metal shaft. Locate the surface speed wheel
and install it on the tachometer’s shaft, sliding the slot in the
wheel’s stem over the tachometer shaft’s metal pin.
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