The latest trends and innovations in Remote Condition Monitoring (RCM) was the topic of a recent webinar presentation by Tracsis Technology Chief Andy Kunzmann for the IRSE (Institution of Railway Signal Engineers) North American section.
RCM can be used to monitor a wide variety of rail assets, enabling railroads to enhance rail safety, reduce maintenance costs, increase on-time arrivals, and improve strategic decision-making across rail asset life cycles. Mr Kunzmann provided IRSE members with insights into the application of AI and machine learning to enable predictive maintenance (covered in our previous blog). He also gave a detailed explanation of typical RCM applications for wayside signal assets: switch machines, track circuits, grade crossings, interlockings, battery banks and ground fault detection systems, summarized below.
Switch Machines
Switch machines are monitored by capturing the motor current during switch throws; these motor current captures provide insights into how the switch is performing. A motor current trace will show if a switch is experiencing excessive friction or obstructions and can be used to measure throw times.
Point indications can also be monitored to detect loss of correspondence and how that might correlate to traffic over the switch. The data captured from the switch is analyzed and an alarm notification is sent to railroad maintenance teams when a switch is operating outside of its expected parameters.
Motor current and throw time data can be plotted to visualize performance trends over time, so that abrupt changes are detected and correlated to root cause factors. This trend data can be used to evaluate and improve railroad asset maintenance programs.
Track Circuits
Track circuits are monitored by continuously capturing the relay coil current and comparing the analog current values to the digital pick and drop status of the relay. The relay coil current can provide insight into how well the track circuit is transmitting the clear value during periods of unoccupancy and how well the track circuit is shunting during periods of occupancy.
Alarm notifications can be generated when a track circuit is showing analog values that indicate a low clear or a high occupied status, even when the track circuit relay is operating in the correct pick or drop state. This can be used as an early indication of eventual track circuit failure. Timestamps of the alarm captures can be used to correlate the specific traffic or other conditions that may be related to the root cause.
Grade Crossings and Interlockings
Grade crossings and interlockings can be monitored using discrete inputs from relay contacts and by interfacing to the diagnostic ports of electronic controllers. Track circuit, relay, signal and warning device status can be monitored, recorded, analyzed, and replayed.
The sequence and timing of inputs and outputs can be analyzed in real time, enabling alarm notifications for unusual activity.
As with the switch machine and track circuit monitoring, Remote Condition Monitoring can function as a remote event recorder for rail grade crossings and interlockings. Maintainers can evaluate the performance of rail assets before heading out to the field, so they are better prepared for what needs to be done and can minimize their time on site.
Battery Banks
Battery banks can be continuously monitored to record voltage levels and to provide alarm notifications when levels are outside of expected ranges. Voltage and current levels can be plotted with timestamps so that related asset activity such as switch machine throws can be correlated to determine root cause of excessive battery loading or loss of charging capacity.
Ground Fault Testing
Continuous monitoring enables intermittent ground faults to be identified, ones that normally would be missed during scheduled site visits. The timestamping of the measurements can assist with troubleshooting to determine root cause.
Find out more about Remote Condition Monitoring for rail assets. Download our brochure.