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3MEASURING PROCEDURE 
3.1 Optical Measurement 
1. Apply reflective tape to the object to be measured; 
2. Move the function selector into the “rpm photo” position; 
3. Press the measurement button and align the light beam with the tape (when the object 
is in motion). Check that the monitor indicator lights up when the tape passes through 
the light beam. Release the measurement button when the reading has stabilised 
(approximately 2 seconds). If the result displayed is less than 50RPM it is a good idea 
to attach more reflective tapes, and then divide the resulting reading by the number of 
tapes applied, thus obtaining the actual reading in RPM. 
3.2 Contact measurement 
1. Move the function selector into the “rpm contact” position; 
2. Attach the appropriate adapter (B) onto the shaft; 
3. Press the measurement button and gently rest the probe tip in the central hole of the 
rotating object. Make sure it is exactly perpendicular. Release the measurement button 
when the reading has stabilised (approximately 2 seconds). 
3.3 Measuring peripheral speed 
1. Move the function selector into the m/min position; 
2. Attach the appropriate adapter (A) onto the shaft; 
3. Press the measurement button and rest the probe tip against the external part of the 
rotating object. Release the measurement button when the reading has stabilised 
(approximately 2 seconds). 
4CONSIDERATIONS REGARDING THE 
MEASUREMENTS 
Cut the supplied reflective tape and remove the adhesive backing. Form a 12mm square and 
apply it to the rotating part. 
a) the non-reflection area must always be larger than the reflection area. 
b) If the part that is rotating is made of reflective material, it must be covered by black 
tape or be painted before attaching the reflective tape. 
c) the rotating surface must be clean and smooth before applying the reflective tape