I am building a CMR turntable and have a question about wiring the bridge tracks. The model uses a pit split rail method to supply power with two 'dead' transition pit track sections that can be wired to be live using an autoreverser. Don't the bridge tracks also have to be wired to an autoreverser since there could be times the rotation of the turntable will not always match the polarity of the stall tracks? Can all sections of the pit rail be connected to the same auto reverser, or do they have to be two separate ones? Not really an electronics whiz, but I understand wiring and can follow directions well. I have read about other ways to power the bridge tracks, but have decided to follow the CMR directions of supplying power through the pit rails as they suggest. Any help will be greatly appreciated.
If there is a split pit rail, and no power is attached to the dead sections - then no reverser is needed. If you turn the bridge end for end, the polarity is reversed because each pickup for it will be on the opposite pit rail. But the dead sections will cause sound decoders to reset.
Normally for a continuous pickup arrangement, that DOES require an autoreverser, one side comes from a continuous pit rail, and the other comes from the bridge shaft, or both pickups are through a pair of wipers and contacts on the bridge shaft.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
So as long as I have the stall tracks wired with the correct polarity, the bridge tracks will always match up no matter which end of the bridge aligns with the stall tracks?
With a split rail, yes. With a continuous pickup plus autoreverser, it will match up when the loco or metal wheels cross the gap fromt eh bridge to the stall track.