Signal processing device (SPD)

SIGNAL PROCESSING DEVICE

Signal processing device (SPD) for the path detection of wheels of railway vehicles ААЕЭ.466948.002 serves for the processing of the output signals obtained from the path detectors of the wheels of railway vehicles of ДПД03 series (ДПД-03Т: output signal - current 0-20 mA, ДПД-03 ¨C output signal ¨C direct current voltage 0-10 V) within the axles accounting systems. SPD is connected to the axles accounting system through the two-wire line RS-485. Logical exchange protocol ¨C ModBus RTU for the slave devices.

SPD maintains the following functions:

- Measurement of the instantaneous values of the detector output signals and setting the response thresholds for the comparator blocks according to the measured values.

During the path of a bogie wheel SDP provides:

- accounting for the number of wheels, which path the sensitivity zone of the detector in the “forward” and “back” direction separately;

- automatic correction of the response thresholds of the comparator blocks after each path of the wheel axle with the speed not less than 1 km/h;

- measurement of the path time needed for the wheel axles to traverse the sensitivity zone (SZ);

- measurement of the output signal levels of the detector and the values of the instantaneous thresholds for the comparator blocks during the inquiry about function 03 (storage registry reading) from the axle accounting system;

- formation of the logical signals for the state of the detector and device;

- the supply of stabilized voltage +(18 +/- 10%) V for the detector.

The data received by SPD during the processing of the output detection signals, is stored in the 16-bit registries, which are reset to zero upon the switching on the electric power supply to the SPD or upon the resetting the micro-controller (MC) with the help of the СБРОС (RESET) bottom.