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I have a trolley line and a main line with a crossover where one line crosses the other. Each line has it’s own transformer. I have cut the 4way metal clip underneath on each side of the main line, leaving the trolley line a connected straight through. Now my main line engine stalls on the crossover. Any way to fix this?

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RoyBoy posted:

If you really must isolate the two tracks, then you will need an extra pickup on the loco. You can put one under the tender or in a dedicated freight or passenger car following the engine. It will need its own pickup and be wired to the loco.

Troubleshooting remotely I wouldn't immediately blame the locomotive until we know that the track is wired appropriately for the scenario. Information provided thus far seems to indicate that the center section has not been fully isolated as necessary for the desired operation.

Last edited by bmoran4
Gpong posted:

I have all my lines grounded in series with each other, so would that still cause shorting across?

Not if using common ground wiring (you probably are).

 

This is the correct way of isolating the trolly and main line:

 

Most locomotives have more than one roller, and those rollers are spaced enough apart to not be affected by the dead center. In fact, Lionel's crossings have had dead centers since their inception going back over a century prewar days.

 

For reference, here is the No. 21 Crossing in 1906 with a dead center:

Followed by the No. 20 Crossing in 1908:

And then the No. 020 in 1915:

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Last edited by bmoran4

I could be wrong, but it seems to me that given what you're trying to accomplish it's inevitable that, no matter how you wire it, there's going to be dead spot on one line near the center of the crossover.  I would switch the trolley and engine to the other line and see if the trolley rolls through the dead spot any better than the engine. If so, you can re-wire accordingly. If not, then the solution is to get power from a remote pick-up as Roy suggested or just remember that you have to increase speed as you approach the crossover (or eliminate the crossover and elevate one line over the other).

If the lines connect anywhere else, and for safety's sake, you might also make sure that both transformers are in phase.  (If the transformers were/are out of phase, that would definitely cause a loco to short/stall if it briefly received power from the other transformer.)  Search the forum on how to do test and correct the phasing.

With a couple of DPDT relays you could wire the crossing so that when a train occupies one route the other route is disabled. The center rail of the crossing would be powered by whichever route is active. Use an insulated outside rail on each route to activate the relay for that route. Wire the power for the route to be activated though the normally open contacts of the relay for that route then onto the normally closed contacts of the relay to the other route and then out to the track. When the train is on the crossing its relay's normally closed contacts would be open preventing power going to the other route.

Forest

Mouser has these. LY2-AC12 Only two left in stock. They have 10 amp contacts. I was looking for one's with 15 amp contacts but mouser didn't have them in stock. They might be able to get them. If you power supply has no high than 10 amp protection you might be ok. You can use DC relays also with the use of bridge rectifiers.

You then will need some insulated track sections or could you ITADS.

What track are you using? If you use insulated third rail this is easier done with Gargraves track as you can cut your block joints wherever needed with a Dremel cutoff wheel. Are you using straight transformer power or some sort of command system? The method that I am talking about is for straight transformer control. You need to lock the e-units in one direction. You will also have to figure out how long the stopping distance is of you locomotives so you can determine how long to make you stopping blocks. I have to think about this a bit. I am thinking you also need another relay to power the center of the crossover. I am going to have to set down and draw this thing out.

Bear with me. I am finishing up the wiring diagram. I am not a user of Fastrak so am not too familiar with isolating the one outside rail or how you gap the center rail. I guess they make separate tracks for that. You will have to have four insulated outside rail. Four isolated middle rails and the crossing will have to have all the jumpers removed from the bottom. Let me redraw the schematic and get it posted. It will need one more relay if you want to power the center of the crossing which is what I think started this thread. Be back shortly.

Forest

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