Device that secures the switch in a certain position. In interlocking it is also safe, with a key, a vice, an electric one, a heel and an unbreakable one. is a device that in a switch ensures the switch blade (switch tongue) to the stock rail. These devices are equipped with all the turnouts for the crossroads and station tracks traveled by passenger trains. In their absence the peaked turonuts encountered by the trains must be attended and the trains themselves must have a maximum speed of 60 km/h. In the event of their inefficiency, specific provisions established by the law must be observed
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