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[quote]QUOTE: Originally posted by cacole Stall Current is a measure dreamed up by decoder manufacturers to insure that they could never be blamed for a decoder failure and being expected to replace it. [/quote] While that's completely true, the 12VDC run current (no load) was 1.1A even, and the current at wheel slip was 1.9A. The stall current number was only thrown out for effect [:D] Running my A-B-A set will absolutely clobber my Zeyphr with a long line of cars behind them. I've measured suge current well in excess of 3A for them when started from a dead stop with 34 cars behind them on DC, and that was a 'short run' with all 3 engines pulling (the B shell is on a donor A chassis). As it is, I can't run all 3 on DCC, and I'm not really happy about it. I'm an engineer. "Probably" isn't good enough. Either the decoder meets the spec for the motor or it won't. In this case, the only decoder that I've seen that does is the long discontinued DH83FX, and those are kinda hard to find. Not to mention part of my goal is to reduce their current demands. Randy- The electrical engineer in me is apalled that LL would put motors with those ratings in the locos and label them as DCC ready, when they knew full well that decoder power density wouldn't be able to compensate. The biggest issue I have is that when the power is disconnected (like if I hit the e-stop button) the flywheels make the motor coast for a while, and that feeds a fair amount of voltage (8-10V if it was traveling fast) on the outputs of the decoder's bridge. The flyback pulses during the on-to-off transition has wiped out the decoders of a few friends. I measured them at over 35V once (didn't have the o-scope scale high enough to catch the actual peak..35V was the upper line on the grid). That's plenty to toast 24V FETs, and it was there long enough to ensure any underrated protection diodes let their blue smoke out. Decoder manufacturers have been very (read totally) unwilling to share the reverse rating of their outputs, or provide enough information so that I could calculate it on my own. The last thing I want to do is spend the money on a bunch (7) of multifunction decoders and burn them out one by one at random times. Yes, I've thought about the TCS no-fault warranty, but I don't want to do that to them, or me. I should never have to replace a decoder that wasn't mis-specified. Summary: I'd love to hear from someone who's tried remotoring these beasts, either with aftermarket or 'new' LL motors. -dave
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