automatic warning device造句

Testimony at the three-day hearing indicated the passenger train had gone through a red light, and an automatic warning device in the cab was not working.
More heavily trafficked crossings have " automatic warning devices " ( AWDs ), with alternately flashing red lights to warn automobile drivers and a bell to warn pedestrians.
As far as warning systems for road users are concerned, level crossings either have " passive " protection, in the form of various types of warning signs, or " active " protection, using automatic warning devices such as flashing lights, warning tones and boom gates.
It's difficult to find automatic warning device in a sentence. 用automatic warning device造句挺难的