What exactly is a signal error?
"It's actually very rarely that the signal itself is wrong. It should show when something else in the system is not working. It can be said that signal failure is a collective name for several different errors that cause the signal to glow red so that the train must stop.
What kind of errors can it be about?
"It could be a fault in a gear or some type of track failure. But the most common is probably that there is something wrong with the track line. The track management is the technology that allows signallers to see where the train is. A signaller monitors the trains and directs traffic using switches and signals. The track line itself runs in the rails and can be disturbed by metal chips or copper theft, for example. Then the signal will show red.
What happens when there is a signal failure?
"Sometimes it is enough for the plant to be restarted for us to get a green signal. If there is a gear failure, we can sometimes have to stand and wait while repairing the gear. In the case of other types of faults and where there is actually no other train in the way, one can get permission from the signaller to pass the red signal in any case. Then the maximum permissible speed is 40 kilometers per hour until passing the next green signal.
It feels like it's often signal failure, is that right?
"Of course it happens, but my view is that we in Western Sweden have a fairly good train infrastructure with upgraded lines and then there are less often signal failures. Our biggest challenge is that we run a lot of trains and have few tracks to and from Gothenburg Central Station. It is not uncommon for us to have to wait because there is a queue or when we are going out because there are other trains that need to cross our path.
- Published 2022-12-14