Dear All,
The old E-units (solenoid driven reversers) don’t operate reliably in the “no-man’s land” region between 0 and 6 volts. (Lionel ZW is actually 8V AC min.)
The solenoid has to drop suddenly (6v to 0v, gravity powered) to assure a catch of the next cog of the circular reversing switch.
The high minimum transformer voltage, while OK or passable with the old inefficient universal motors, causes the newer DC can motors (driven with rectified track AC) to fly down the track.
This high speed makes it quite hard to do rolling stock switching (shunting, for you Billington E2-Class 0-6-0T locomotive fans).
I have DIY fixes for excessive 3 rail speed:
Reduce 2-motor (Diesel) speeds by wiring them in series instead of parallel. (Some have installed internal DPDT switches to choose series or parallel.)
Reduce single motor (steam) speed by adding back-to-back diodes pairs in series between the reverser board and the motor.
http://www.bachmanntrains.com/home-usa/board/index.php/topic,15415.0.html (scroll down)
Reduced motor voltage also gives brighter lights and more smoke.
Hope this helps.
Sincerely,
Joe Satnik
Edit: added “gravity powered”