Diesel Locomotive Engine Working Performace

I thought some of you might find this interesting.

Just click watch on you toob.

Pretty much correct...but a lot of variation, there.

Older locomotives have DC traction motors. AC electric motors was something that EMD played with in the 1970s...didn't work out; I don't know why. Conrail had a few early AC units...they had been scrapped long before I showed up.

Second-generation AC power, the EMD SD80MACs, had shown up about the time I did. They were semi-prototypes...Conrail was the only buyer, and was well satisfied with them. I know I was, as an engineman. Quiet, smooth...didn't have to watch amperage, unlike with DC traction motors. There were a lot of things you could do with AC power that you couldn't, with DC. Like, put power on as you're releasing train brakes, to prevent unplanned rolling back.

With a DC motor, you could have stall burns on the windings, if you had power fed while the motor was stationary or held speed below specified minimums over a long time. For whatever reason, and I don't understand the specifics...AC motors, at least the EMD ACs, were immune to that. Absolutely simplified operation.

Quiet and smooth and easy...tremendous dynamic brakes. Whisper-cabs.

The other railroads didn't want them.

CSX reluctantly took all our SD80MACs when they and Norfolk Southern bought and divided Conrail. Their heart wasn't in it...they got one order of SD70MACs (SD70s with AC traction motors; that wasn't part of the original design for the SD70s) and they did it on the cheap. As I understand it, one rectifier pack per TRUCK, not one per MOTOR, as the Conrail locomotives had.

They didn't work out, and CSX sold them (or cancelled the lease on them) and sent them to Mexico. It then went looking to get rid of the SD80MACs. All kinds of emotional reasons: "Orphans." "Conrail JUNK." "EMD's gonna fail, so we'll get rid of them."

They sold a few, and took others out of service or kept them in reserve. By this time, GE was offering AC locomotives. For whatever reason, CSX liked GE power...probably because of kickbacks for purchasing officers. Their product was SCHITT. GE makes a lousy clock radio; a lousy refrigerator; a lousy light bulb. And a lousy locomotive, that lasts about half as long as EMDs did, when EMD was owned by GM.

But I digress. When someone talks about "diesel locomotives" he might as well be talking about "cars." Which car? An old VW Beetle, or a new Toyota Camry? A Model T or a new E-Mustang?

So much difference.