Premier Norfolk & Western J Steam Locomotive
4
Ensuring Proper Power to Track Polariy
Figure 3: Proper 2-Rail polarity wiring and locomotive orientation
Changing Track Polarity Inside the Locomotive
Figure 4: Changing the polarity with the locomotive polarity switch
For 2-rail DCS operation, it is important that the polarity from the transformer to the
engine is properly configured. Correct polarity can be accomplished by ensuring that
the wiring from the TIU to the track and orientation of the locomotive when sitting on
the track follows the illustration in Figure 3.
To TIU Black Terminal
To TIU Red Terminal
(The DCS Polarity
Switch should be moved
toward the rail that is
connected to the red
terminal of the TIU.)
DCS Polarity Switch
Failing to properly configure the
polarity will result in the
locomotive starting in reverse
instead of forward or not receiving
the DCS signal. Should this occur,
it is not necessary to swap the
wires from the transformer to the
track or reverse the locomotive’s
orientation on the track itself.
Instead, simply slide the polarity
switch on the bottom of the Tender
as seen in Figure 4.