EntityQ5251114· pop 5· linked from 116 articlesdefect detectorSign in to savedevice used to detect defects on trainsConnectionsrailway trackEntitysignalling controlEntityrubber-tyred metroEntitytrainEntityrailway stationEntityinfrastructureEntityrail transportEntitytrack gaugeEntityrailEntitylevel crossingEntityrailway platformEntityrailroad switchEntityrailroad tieEntityoverhead contact lineEntityrolling stockEntityrailway signalEntitythird railEntityrailway electrification systemEntityrailway turntableEntityUnited States Department of TransportationEntityCategoriesRailway safetyTrain protection systems