Pictures from a so called "power trailer" (loaded in USA but maybe European technology). When the different trailers are assembled, including the control room, you have a power plant that can be removed at any time to a different place.
Besides the acronyms I am trying to make sense of the drawings (for what is it and for what it is not ). The coil shown after the actuator, is it an inductor, a tubing coil or...? Not intuitive except for insiders at Wabco, I guess.
If you look at an articulated lorry (UK speak), in the area between the cab on the tractor and the trailer, there are several air and electrical connections.
These connections are made with long curly tubes and cables.
Look at the pictures here: https://www.trucknetuk.com/phpBB/viewtopic.php?t=24823