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Friday, April 03, 2009

Birney Project ~ Wiring for Trolley Pole Reverse

Fortunately, the Birney cleaned up nicely from the April fools day disaster ;-P. So now we can continue with the wiring. I'm going to use a nifty technique known as "Trolley Pole Reverse":

Trolley Pole Reverse wiring is used with live overhead. The direction of the trolley is reversed by simply switching poles, no need to switch polarity in the track! The way it works is; one pole is wired to one of the motor leads, and the other pole is wired to the other motor lead. When one pole is up in contact with the positive overhead, the motor lead it is wired to becomes energized with the positive electrisicles. The other pole is down making a connection with the holddown hook on the roof. That hook is part of the metal car body that is energized with the negative electrisicles from the wheels in contact with the negative rail. So that pole is energizing the motor lead its wired to with the negative electrisicles, making a circuit! Then, switch the position of the poles so the first is down and the other pole is up, the polarity of the motor leads are reversed and the trolley runs in the opposite direction! Cool huh?

Utah Pacific #CLU-96 Constant Lighting Kit wired in series with the motor provides 1.5 volts for reversing headlights and taillights as well as constant lighting for the destination board and route number signs. I had to omit the interior lighting, the unit is at capacity with the 7 bulbs its already lighting. Maybe someday I'll be able to figure out how to light the interior but, if I was to do it all again, I would go with LEDs. They last much longer, I'm not looking forward to fishing out a burnt out bulb out of the spaghetti of wiring shown above. The bulbs are glued in place with Elmers White Glue. Elmers is also used to glue the wires to the ceiling so that the dont hang down in the windows. Elmers hold really well but is also easy enough to remove.

2 Pin Micro Mini Connector from Miniatronics (Code: 50-001-02) allows the motor/truck assembly to be detached from the body for maintenance. One pin is wired to one trolley pole and the other pin wired to the other pole/constant lighting module. The negative charge from the rails transfer through the mounting screws to the trolley body and hold down hooks.

Add some power and "bling"... yessir! "Bling"!

Dandy