Contact Wire Recording System (CRS)

The Contact Wire Recording System (CRS) enables precise measurements at high speeds. It is an excellent tool for evaluating newly built standard lines and for the difficult, less frequent recording of conductor rail lines. The CRS determines the position of up to eight contact wires optically. With active lighting and automatic cleaning features, it operates day and night, even in highly polluted areas. Inspection runs can be carried out during regular operation since the system is designed to provide reliable data at speeds of up to 250 km/h.

17.5 cm pitch at 250 km/h

The CRS sensor is based on laser scanners that use the phase shift measurement technique. A rotating polygonal mirror assembly deflects a modulated laser beam to the contact wires, covering a 70-degree scanning angle, and collects the returning radiation for analysis. Each measured distance value, together with the corresponding scanning angle, yields the position of the contact wire. A scanning rate of typically 400 Hz ensures a high measurement density. Even at a travel speed of 250 km/h, the system measures one height and stagger value every 17.5 cm. The extraordinary measurement rate of one million points per second yields approximately 1,800 points per scanning line, resulting in at least six values per scan on typical contact wires. A combination of at least two linear transducers can measure the car body’s roll on the bogie. The CRS software processes the data and calculates the stagger and height values in relation to the track´s center. 

Reliable operation even under extreme conditions

The CRS recalibrates itself before each scan. This ensures precise and stable results, even at extreme temperatures and over long periods of time. The system's housing is hermetically sealed (IP67). The CRS is eye-safe according to IEC 60825 standards. The laser automatically switches off when the mirror stops rotating.

The CRS can be equipped with climate control and/or semi-automatic cleaning units. The system is available as a standalone device or as part of the Contact Wire Inspection System (CIS), which is a multi-sensor system combining measurement technology for wire wear and position, as well as optional pole detection.

Fraunhofer IPM’s services include adapting the system to country-specific requirements and training operating staff.