USA: Schenck Process has obtained US legal-for-trade status for its MultiTrain LegalWeight in-motion wagon weighing system. This uses instrumented concrete sleepers with high-precision load cells to measure the vertical force applied through the rail with an accuracy of 0·2%.

It requires 50 m of straight and level track, works in temperatures between -30˚C and 50˚C, and can weigh vehicles running at up to 22 km/h. Passing trains can run over the track at line speed.

The use of a ballast-supported design instead of traditional concrete foundations means it can be installed in less than a day, minimising interruption to revenue services. The supplier says the cost of installation is also 25% to 33% lower than for traditional pit scales.

As an option, it can provide unbalanced load detection for both front-to-back and side-to-side loading.