Landquart SBB - Signal Box

The contacts of all relays in a signal box are cleaned by hand once a year. During the night, when there are large time windows between switching operations With a rag, that goes very quickly. When you look closely, there are small black dots that then disappear. This happens regardless of whether the respective contacts are actually used in a circuit or not. There are contacts that toggle several times for each train journey, those that toggle only a few times a month, and those that only toggle on rare occasions. About every 10 years, the relay sets are revised and replaced by overhauled ones. By far, the most often toggled the feedback relays from the railway barrier flashing lights. As long as the alternating blinker flashes at a barrier, these relays wobble, as can be seen in the video. Switzerland, January 18, 2022. (12/13),