>If there are still problems with the control systems, why? Gensets have been around for several (5+?) years now so the software should be patched.

Several years ago I was the supervisor of a contract switching operation. One of our operations was to provide an engineer to unload UP shuttle trains about once a week at a new elevator. One day the engineer I trained called and said he couldn't control the train and was operating it manually. Normally, we used the "slow-speed" system to push the train at .12 mph through the elevator. I jumped on the trailing units and had him try to use the slow-speed system. I finally found that one of the xCNW ACs (one of the first built?) apparently was unable due to software or hardware to control that low a speed. After isolating it, the remaining units worked fine. I can say for a fact that the UP, SP and CNW GE-AC units all had different screen arrangements (hardware) and obvious software differences. In addition to trying to get all the same locomotives with the same software version, there are also different generations of hardware. How many times has it been neccessary to abandon a printer, scanner or some other computer device because it is orphaned and no longer supported? From what I have seen so far, the gen-set design does not seem to have any model mass produced using a basically identical proven design.

>"Chopper" controls are common if not standard in recent rail equipment. Nothing new there. Shouldn't have any different effect on gensets than on anything else.

I'm not arguing that chopper control has some advantages. My question is what are the losses in a chopper control system compared to the former standard hard connection arrangement? I think that too many times electronic controls are used to be "modern" instead of using the most practicable system - regardless if it is new or old technology. I think software based systems often allow far too much "tinkering".