Kong Lingyong, deputy director of the workshop, looked at the idea of the staff in his eyes, and thought a lot of solutions, but the effect was not obvious. In order to solve the problem that plagued the safe production of the shunting operation, the idea of "technical defense" to protect the safety was carried out, and the wisdom for the construction of the "smart West machine" was made. In March 26, 2016, he was inspired by the alarm of the supermarket exit in a shopping mall. Back to the unit, he exchanged design ideas with the workshop worker Feng Liang. After repeated tests and improvements with the car, they made times police with "brake train", "electrified brake" and "traction condition". The "three defense" alarm. The device adopts the principle of infrared detection, adding induction device on the locomotive sluice and the main handle. Without affecting any operation of the original handle and equipment of the locomotive, the device only detects the information of the position of the handle of the locomotive, and passes the detected information to the internal chip of the alarm device for logic processing, and realizes the various hands. When the handle position is mistaken, the voice alarm function is given, and the driver is reminded to operate according to the standard. At present, 10 HXN3B diesel locomotives, which belong to the workshop, are equipped with a "three defense" alarm, which eliminates the trouble of 78 shunting drivers, including Shang Wei, in the shunting operation because of the misoperation of the handle.