As a secondary condition, EN 999 stipulates the followingminimum height:H
D = 15 x (d - 50) mmApplication of this formula is necessary as the leg diameterchanges with the distance from the floor. Here, d is the resolu-tion of the FLSC (d is dependent on the distance from the scan-ner).The resolution of the professional scanner must always be determined atthe point of the greatest measuring distance, i.e. at thegreatest occurring protective field length SL

MachineProtective field

max. protectivefield length max .Based on the working principle of the FLSC by means of radialscanning of the surroundings, a resolution is produced whichdecreases as the distance from the sensor increases.Thus a protective field length SL greater than 2.70 metres (onlyup to this distance is a scanner resolution of 50 m guaranteed) makes a certain detection height necessary. In this way it ispossible to compensate for the lower resolution with greater legdiameter.These correlations between SL, H
D , H
S and C are shown graphi-cally- in the adjacent diagrams. In this, H
D is the height of thescanner plane, measured directly on the sensor.With horizontal mounting there is no risk of unwanted accessingat mounting heights below 100 mm (for example crawling under the scanning plane). To prevent children from crawling under-neath, the maximum mounting height is 200 mm. Mountingheights of less than 100 mm are generally not to be recom-mended, as in such cases it is possible that the scanner mayaccidentally shut down as a result of the increased dust concen- tration directly on the floor. For these reasons this mountingrange is often preferred, and consequently is identified as suchin the diagram. Using the diagram: Define the maximum protective field length SL
max in your layout.Shift the right Y-axis (H
D ) in parallel onto the located value SL
max .Then place the desired scanning plane in the remaining areashaded grey. The plotted scanning line must not leave the greyarea at any point.Within the area shaded grey in the diagram any mountingorientation is possible, provided it does not impair the safetydistance. Resolution of the scanner at the point of longest protective fieldlength SL.

875850 12003002.9 m3 m2 m4 m 1000 C1001003000 HS (mm)HD FLSC scanning area Longest protective field length Preferred area for horizontal installation

Correlation between protective field length, resolution of sensorand height of scanning plane
Technical Description • FLSC © FIESSLER Elektronik OHG • Doku Nr.628 R.H.

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