© Copyright TuControls Ltd 2015

Terms of Business and Conditions of Sale (PDF)

TuControls Ltd


Essex CO11 1UR

(44) 1206 395661


Standard Conditions of Purchase (PDF)


This smart sensor measures the movement of a rail or sleeper in real time, increasing safety and allowing efficient targeted maintenance of vulnerable tracks in critical areas.

This Movement Sensor has been developed for Network Rail over the past year, with Product Innovation Ltd, a UK based product development company.    The device incorporates the latest technology to monitor the effect of voids below railway sleepers by integrating with the new Network Rail Intelligent Infrastructure.  Following the successful demonstration of a prototype, pre-production samples were ordered, the first of which was installed on live track at Witham in July 2014. Since then six more units have been supplied to allow Network Rail to investigate the optimum combination of standalone and multiple installations at turnouts and crossings.

The Void Meter is simple to install, both physically and electrically, and provides a real time output in the form of a 4 - 20mA signal.  It measures the vertical position of a sleeper or rail and outputs this continuously allowing for data loggers or direct remote reading. The range of position measurement is 100mm which is sufficient to allow both upward and downward movement of a sleeper to be monitored. The resolution is 0.5mm.

All the mechanics and electronics are contained in a metal casting. Emerging from the casting is a moveable stainless steel rod which is sprung downwards towards the sleeper or rail. As the train passes and the rail moves the rod follows it. The resulting position of the rod is measured within the casting itself and then converted to the 4 - 20mA signal. The sensing of position uses a Hall Effect microchip that allows the electronics to be totally encapsulated thus making the product immune to the effects of weather and vibration. Patent applications have been filed for the product.

The Void Meter will be of interest to any Rail Company that is working to make maintenance more effective.

Specification Details (PDF)

The Void Meter on trial (YouTube)