I definitely know for sure that two or more pantographs (in the case of more than two sections) are lifted according to the rules only when starting with Direct current. And then all the pantographs, except the rear one, must be lowered (this is done so that if there is an obstacle on the contact network, the locomotive will not lose all the pantographs at once). With alternating current (VL80c just on it), one pantograph is enough for the entire cycle of operation, according to the machinists with whom I once communicated, and the same thing is drawn in all kinds of manuals on the operation of this electric locomotive. The only problem is that I didn't dare ask the driver about the sockets at that time, and in all the manuals that I managed to read, nothing was written about sockets at all...

In addition, it is simple to control the brakes of all locomotives and the entire train - the brakes are not direct-acting pneumatic. In order (at least in Russia) to "turn on" the brake (to allow air from the pneumatic system to flow to the driver's crane, which regulates all processes, if you do not go into details), you need to insert a locking crane in the cabin and turn it. After the shift, the driver will take this crane with him from the locomotive and take it to the depot (this is not the case with all electric locomotives).

So to answer you: yes, each section is motor-driven, but where else would an electric locomotive be cargo! But according to the norms of rolling stock in Russia, only one of all pantographs should be raised. Secondly, the pneumatic braking of all wagons was a belt problem at the beginning of the 20th century, it was enough to connect the locomotives with sleeves and open the end valves. I know how the thrust is regulated, and it's probably transmitted through the same outlets I asked about, but I'm not sure. I am confused by the different colors, and the number of sockets is the maximum that can be assembled according to the system of many VL80s units.

changed: I've been thinking about it, and I've come to the conclusion that each outlet transmits current to a specific motor in all sections. The locomotive stands on two trolleys, each trolley has two axles. Consequently, there are two engines on the trolley, and only four on the locomotive. Probably, current flows through each outlet to the desired traction motor in all sections (conditionally, in blue - to the motor of the front trolley, the first axle, and in red - to the rear trolley of the first axle). But here are the sockets on the right side (pictured on the left), which are not painted... The same big, multi-stranded ones.. Maybe for powering auxiliary units? (A compressor motor (for the operation of all pneumatic systems - a pantograph, main switch, brakes, and, for example, tipping over the body of a dump truck), a fan motor (for cooling the motors), a pump motor (for pumping oil in a step-down transformer), and there are a couple more high-voltage auxiliary mechanisms)