@Strap Hanger posted:That's strange. I run my red and green PS2 Lo-V sets occasionally under the Christmas tree (powered by a z-1000 without DCS) in conventional mode and they always start up properly in conventional without the speed control engaged
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From what you are saying, the PS-3 engines revert back to command speed control even without receiving a DCS command signal. That's a ridiculous design by MTH and is very different from the PS-2 models.
There may be a different interpretation of Speed Control. How do you know Speed Control is NOT engaged on your Christmas Lo-V with a Z-1000 controller? Speed Control in PS2/PS3 means that the flywheel tach stripes are used as tachometer to regulate speed. In command mode, the DCS remote explicitly sends a sMPH target speed. In conventional mode, the PS2/PS3 electronics measures the track voltage and maps that voltage to a sMPH target speed.
When Speed Control is turned off in conventional, the flywheel stripes are ignored (for speed regulation) and whatever voltage level is on the track is applied to the motor... in other words no feedback. There is no ability (or reason) to turn off Speed Control in command mode because the engine would rocket at 18V without the benefit of the tach feedback. In fact, a common problem is the DCS command engine that rockets irrespective of commanded speed. In 99.9% (I'm making this number up) of the cases this is because there is a problem in the flywheel tach. In other words, the electronics gets no feedback from the tach and thinks the engine is not moving; it then applies more and more voltage which makes the engine run faster and faster until it flies off the track or worse.
The PS2 and PS3 Speed Control should behave the same.
