The hoses are just hoses. For a given type of brakes, there are the same number of pipes on both sides (at some point the brake systems changed from 4 to 3 pipes/hoses I believe). Each side is redundant. You only need one of each connection to be made. If there isn’t a hose where you want it, you just unscrew it, move it over to the pipe you want it at and screw it back in. So at least 3 hoses are connected between each engine. It is easiest if all pipes have a hose. By the way each pipe has a valve behind the pilot sheet to open or close the connection to the next engine.
From left to right a normal hose arrangement (26 air) would be:
Sand
Independent apply-release
Actuating (bail-off)
Main Res
Trainline
Main Res
Actuating
Independent
Sand
This is for air-operated sanders. Later on, the MU cable transmitted the sanding needs, and the hoses were removed.
Only one side needs to be hooked up. I usually hook up both sides, seems to work a little better. In winter, having both sides hooked up keeps snow and ice out of the gladhands.
The chances are pretty good that, given the same tire sizes, at any given throttle input your XYZ Super-duper Blow-em-all-off-the-road automobile will run at the same speed as all other XYZ Super-duper Blow-em-all-off-the-road models. So also, all gear ratios being the same - more on this in a moment - each locomotive in a lash-up is electrically connected to the lead locomotive via the Multiple Unit (jumper) cables and will therefore respond identically to uniform control signals. When, for instance, the throttle in the lead loke is advanced from, say, notch 7 to notch 8 every loke in the lash-up advances from notch 7 to notch 8. So also will all these lokes dump sand simultaneously.
I don’t know about the “loading” factor involved but I have always believed that one of the reasons that the diesel locomotive has “slow” disconnect circuits is to allow a “loaded” unit to overload for a short time while the Multiple Unit system stabilizes and each locomotive is running at a standardized performance. In recent years this function is controlled - or at least assisted - by multi-processors.
One of the contributing factors to Baldwin’s demise from the diesel locomotive market was that their pneumatic control system was incompatible with other manufacturer’s electrical control systems. Baldwins ran great with other Baldwins but to get a Baldwin to operate with an EMD, for example, required a separate locomotive crew which negated the monetary savings of Multi-uniting.
Now, about gear ratios: following the demise of the passenger train some railroads opted to regear their passenger locomotives to freight gearing which allowed them to get a few extra miles out of these E- and PA units which allowed them to forestall the purchase of new freight power. This was a dubious success. There are undoubtedly others but Erie/Erie Lackawanna comes readily to mind and, I beli
Aside from air and electrical connections, finally the cross walk chains must be connected and a couple tests performed. First is a load test to see that each locomotive is loading as commanded from the controlling locomotive in each direction (it’s impossible to tell which direction an engine is loading standing still and if a jumper is defective it is possible to have an engine in the consist that wants to go the other way) . Finally an air test is performed to make sure the engine brakes all release, apply independently, then release, apply and bail off in response to train brake applications. Then a leakage test is done to insure the brake pipe does not like beyond a certain amount (depends on the rr but usually no more than 5 lbs per minute.
You explanation is excellent, brought back a few memorys.
There is a letter F which desinates the front of the unit, In the cab is an electrical rotary switch for placing the unit (If my memolry recalls) when selected, lead Cab end forward, lead long hood forward, trail cab forward, trail long hood forward, dead in transit. After GP 45s I dident care as I retired…John
