I tried measuring the RPM of a snowblower engine. I adjusted the rate until the white stripe I placed on the pulley was stationary, but the video was showing three stripes, not just one. What would cause this?
@peterpauldonoghue70242 жыл бұрын
According to the instructions on the App “YOU SHOULD BEGIN MEASUREMENTS FROM THE LARGEST FREQUENCY THAT IS POSSIBLE FOR THE TESTED FAN. TO REDUCE THE FRAME FREQUENCY, SIMPLY CLICK AND HOLD THE BUTTON.” “The observed pattern will change. For example, if the actual speed of the fan is 2660 RPM, and you began measuring the frame frequency at 11000 RPM, then as you reduce the frame frequency, the following still images will appear:” “Four or three marks can be seen at other frame frequency; for example, three fixed marks can be seen at a frame frequency of 3990 rpm (real RPMs multiplied by 1.5), four marks at a frame frequency of 3546 rpm (real RPMs multiplied by 1.333.) and five marks at a frame frequency of 3325 rpm (real RPMs multiplied by 1.25). The wrong conclusion can be made when defining the RPMs by increasing the occurrence of the frame frequency. For example, at a frame frequency of 887 rpm (real RPMs divided by 3), one mark is visible. This frequency can be misleading, since after multiplication or division of this reading by 2, one may obtain the same pattern as what is observed at the correct frequency (in this case, at 2660 RPM). THEREFORE, YOU SHOULD NOT START WITH A SMALL FRAME FREQUENCY AND THEN INCREASE IT.
@markrainford12193 күн бұрын
Alcohol.
@peterpauldonoghue70242 жыл бұрын
Hi I’ve downloaded this App But am having problems.. I understand that the RPM can be seen stationary at a ‘Harmonic’ below the true speed! But I can’t seam to get a reading Outside !! I’m on an iPhone 5s Does the App need the phones light ? Is it the light that flashes at the required rate ? Or is it the ‘frames per second ‘ on the camera ?