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I found an Aristo Craft reversing set that includes two rerailers with diodes installed and the controller.

My question is regarding the warning about the last car can't have lights. So does that mean a Doodlebig can't run with a heavy weight and the lights?

Why are lights a factor in this set up?

Thanks,

Bill
 

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Probably because the car will stop in the dead section, and until it is renergised by the timer there is no power to work the lights. I use on of these units on my Tramway (Trolley) line.
 

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I have cabooses with lights and have no problem with the aristo reversing unit.

The caboose light will be on at one end of the run and off at the other end due to the diodes, but no running problems have ever occurred from running lighted cars.

However, if you have tied an engines power to a car with power pickups, then there is a possible problem as both the engine and car must travel beyond the diode before the train stops.\

Solution is longer stop track, or do not tie the engine to the first car.
 

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The thought is that when the engine passes the diode it would normally stop. But if a car with lights has pick-up on both sets of axles, and the front axle toward the engine also gets past the diode before the engine comes to a stop, electricity will travel up the railcar axle that is still out past the diode, pass through the car, come down the axle that is within the diode, make its way to the engine, and let the engine keep running off the end of the track. This can and does happen.

I have a leap frog section where the trains slow down before leap frogging. This is accomplished by routing the power to the leap frog section through several diodes and a in-rush thermistor. When I run heavyweights with lights, each time one of the heavyweights straddles the leap frog section and the main line, power flows from the main line up the back axle to the front axle to the leap frog section and the train speeds/slows each time a heavyweight enters that section. Same idea.

In the case of the reversing unit, the trick is to leave a non-lighted car between your engine and any lighted cars.
 

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What may happen is this: when the loco stops on the diode controlled section at the end of track, and a car is drawing current outside of that section, the reversing unit will do nothing.

Remove that car and things should revert to normal operation.

cheers
 

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Posted By Tom Leaton on 12/04/2008 11:59 AM
What may happen is this: when the loco stops on the diode controlled section at the end of track, and a car is drawing current outside of that section, the reversing unit will do nothing.

Remove that car and things should revert to normal operation.

cheers

Current draw has no effect on the reversing unit, unless you exceed its capacity and "smoke it." All the reversing unit does is switch the polarity from the power pack to the track at a regular interval that is adjustable by the user. If you want your train to sit at the end for 30 seconds and it takes 30 seconds to get from one end to the other, you simply set if for 60 seconds at which time it flips polarity to the track and the train takes off in the other direction.
 

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I believe I have to disagree about the current draw and the reverser. Of course it depends on the reversing unit. IIRC, the Aristo-Craft unit does not start the delay timer until it sees a zero current draw. I can set mine to delay at the end for about ten seconds. If I have about 25-30 feet of track, it takes longer than ten seconds to get from one end to the other. But when my trolley gets to the end, it waits for ten seconds, then starts back. If I only have six feet of track, the same setting still waits ten seconds at each end.

If the timer simply ran and reversed at each time cycle, when I have a 25-30 foot run, and the timer was set for ten seconds, the trolley would never get to the end of the line. It would stop and reverse whenever the timer ran out.

If I had a two-car trolley and the trailing car had lights, the lead car would stop when it gets to the diode, but the trailing car is still on the powered track and the current draw of the lights will not allow the timer to start, so it makes one trip and stops.


Of course it all depends on the design of the reverser unit.
 

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Sorry Micheal, but I use cars with lights using track power and I have regular 33ma bulbs in my bumpers and I have no issues with the Aristo reversing properly. My unit simply is a timed relay with no track feedback.

Did Aristo make 2 different reverse units that operate differently? They have 5 types of the black 27mhz TE and all have the same part number.
 
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