Measurement trains and trial trains are used to observe and control the railroads. These trains run with a maximum speed of 120 km/h = 33,3 m/s. To establish the position and presence of the switch in the track in the measuring data, a detection/ measurement should be carried out. When running the distance to the inside of the rail is measured.
The use of (analog) inductive sensors often causes false, unaccurate and unreliable measurements. Although an inductive is capable to detect the switch, in this application the measuring range, measuring speed and measuring accuracy of an inductive sensor leaves much to be desired. By applying our LAM70 series industrial laser sensors, the demands of the measuring variables are met.
The SP LAM 71.101 is an industrial distance laser which is capable of performing a reliable distance measurement in the direction of an approaching switch on the railroads. With the high measuring frequency of 40000 measurements a second, a repeating accuracy of 25 mm can be reached. This results in 12 measurements per moved centimeter if the train is running with a speed of 120 km/h.
If measuring accuracy is more important than the measuring speed, the measurements can easily be averaged. This benefits the repeating accuracy significantly. In this case a measuring speed of 1 kHz (1000 measurements per second) results in a repeating accuracy of ca. 10 mm.
Because of the compact housing of this distance laser can be mounted discretely on the measurement train. Moreover the sensor housing has a IP67 protection degree. This means that no water and dust can penetrate. With a maximum measuring distance of 270 meter, an analog 4-20 mA output, 2 digital contacts and RS232/RS422 interface this type of laser sensor is deployable in countless applications.
