Weight is Paramount! - Mini Measuring-Block for QS3

To measure elevator ride quality according to ISO 18738, the acceleration sensor requires a contact pressure of 60 kPa against the cabin floor (this is the reason why one cannot execute an ISO 18738 compliant measurement with a smartphone). Our sensor QS3 achieves the contact pressure when clamped to the transportation case during the measurement process. Alternatively, our new mini measuring-block, which is available from now for immediate delivery, features very small dimensions aiding transportation in your hand luggage on airline flights.
platte_seite.JPGISO 18738 "Measurement of Ride Quality" for elevators is an international standard for normalized measuring of handling characteristics in elevators. The human perception of an elevator drive is simulated by the appropriate evaluations. An accelerometer for this task must feature high sensitivity and accuracy, because humans have also very sensitive organs for detecting vibration and noise.
Therefore ISO 18738 precisely defines the requirements for the accelerometer to be utilized. Thought had also been put into the way, vibration transmits into people during the elevator ride. A person usualy experiences an elevator ride standing on both feet. The feet exert a certain pressure on the cabin floor; it is this pressure which has to be applied by the accelerometer on the cabin floor according to ISO18738. As we stand on two feet and the standard assumes an average weight of 68 kg for a person, each average foot produces a pressure of about 60 kPa. This is precisely the pressure required by the standard for the accelerometer. If the bearing surface of the acceleration sensor on the cabin floor would be as large as an average human foot, the sensor would have to weigh about 34 kg to fulfill the requirements of the standard. handy_verboten.pngIf you were to execute a measurement with the acceleration sensors of a smartphone (which is not permissible according to ISO 18738 because of the technical properties of the sensor) according to ISO 18738, the weight of the phone would have to be around 15 kg to provide the required pressure.
koffer_oben.JPGPressure is defined as force per surface-area; when the surface is becoming smaller, the force and finally the weight may be smaller. For this reason the regular measuring plate of our sensor QS3 (transportation case) features three relatively small feet. This allows the weight to be 3 kg only, substantially less than the 34 kg required if the case stood on its full surface. The use of the measuring plate is mandatory for measurements according to ISO 18738. Failing to use the measurements renders measurements de facto invalid. Moreover, such measurements show irregular vibrations between sensor and cabin floor which would not otherwise occur and even distort the measurement results unnecessarily.
platte_unten.JPGThe regular measuring plate is comparatively large with edge lengths of 290 x 230 mm. This may render the kit just somewhat impractical when traveling. For this reason we have developed our new mini measuring-block for the QS3, which impresses with very small dimensions; it is in fact only slightly larger than the actual sensor QS3. Just like its big brother, the mini measurement-block stands on three small feet, to keep its weight as low as possible but still meet the requirements of ISO 18738.