While at one of my favorite train watching spots yesterday, three BNSF locomotives stopped nearby. They were pulling a mixed train of box cars, hopper cars, and tank cars.
The lead locomotive was a GE C44-9W. Or at least I think it was. The engineer spooled up the diesel to what seemed like very high revolutions for approximately 10 minutes and then backed it down. The train remained stationary. What was h/she doing?
My GUESS!
Charging up the air brake system - may have had, for whatever reason, a Main Resevoir pressure reading that was below the acceptable limit.
Modern locomotives often rev up their engines for no apparent reason, not just low air pressure.
The computer may have decided to warm the engine or initiate a turbo cool-down cycle, both of which I have seen given as reasons on the computer screen.
Sometimes the computer does not give a reason.
Our rebuilt 60s are always screaming, it seems. But they settle down by the time you have to move again.
In what ways is the locomotive, i.e. diesel, motors, controls, etc. controlled by a computer(s)?
Pretty much all of it.
Once upon a time control was all analog electrical and mechanical. Lots of switches, relays, flyball governor, rheostats.
In the 1960s, some solid state items got added to the mix. Transistors and diodes.
In the 1980s, integrated circuits were added, and finally microprocessors.
In the 1990’s electronic engine controls were introduced.
There’s really nothing left that’s not under the control of a microprocessor.
Next time you take your daily driver to a shop - have them plug a full function OBD2 (On Board Diagnostics 2nd Generation)reader into your car’s OBD2 port - you will be amazed at all the functions that are measured and controlled by the computer. Without computers today’s internal combustion engined - be that gas or diesel don’t operate.
The ‘cheapie’ OBD2 readers you see On Line and at Auto Parts stores, show a number of the generic mesasurements, the manufacturer specific readers reveal all - what all is measured and used to insure proper combustion of the fuel will amaze you.