More Than I Can Chew

[Anonymous]

OK, I give up. I need help from a relay logic guru. I have a loop of track that has a two direction passing siding. One train moves around the loop and enters a block and stops. The other train starts and moves around the loop in the opposite direction until it enters it's block and stops. The cycle starts again. To this I added another slightly diffierent passing siding. I suspect I can control both of these passing sidings with sealed relays purchased from Braun Manufacturing. The kicker here is that I have combined both passing sidings with a main outside main line and I have been loosing what little hair I have left trying to come up with a wiring scheme that will not allow any of the four trains to collide.

I would be happy to fax the track plan to anyone who would be willing to help. I keep getting asked, "Hey dad, when are we going to run the trains" and I have no answer.

[Roger Bielen]

First things first,.

hirailr25 - WELCOME TOP THE FORUM

I don't have an answer for you but hang in here there are others that use blocks that probably can offer advice.

[lionelsoni]

It sounds like you're doing something like what was discussed on this recent topic:
http://www.trains.com/community/forum/topic.asp?TOPIC_ID=52970

Yours seems a little more complicated, and I don't feel like I fully understand it. A fax doesn't work for me. Can you e-mail or just plain mail the track plan? Or maybe take another stab at a verbal description, in more detail?

[cmrj]

Hi for starter's your going to need some insulated track sections in order for the train's to do the work of makeing the relay coil or coil's . It is going to be like a basic holding circuit used in some elec. motor starter's. also Lionel IR detector's could possibly do this as well as the station delay control . layout diagram would help to get a better idea of wireing. You will need to control switch to throw once and anti derail will throw back if you are using Lionel switches. cmrj [:)][:)]

[eZAK]

hirailr25,

[#welcome]

I would be happy to take a look at your track plan.
Send me an email at [e-mail] and/or I can provide you with a fax #.

[Anonymous]

Thanks for the Welcome and thanks for the responses. I will attempt to get the hand drawn track plan scanned by a friend of mine and attach it to the next response.

I am seeing the light at the end of the tunnel and I hope it is a train.

Thanks Again.

[lionelsoni]

I just got Gus's track plan. The important thing about it is that there are four double-ended sidings leading to a mainline loop. All four trains have to go through the same segment of the main line; so they can run only one at a time. The trick is to get them to take turns and to return to the same sidings from which they came.

Gus has 10 24-volt DPDT relays. He doesn't say whether AC or DC; but it doesn't matter for what I will propose. He says he wants to use infrared detectors; but I am unfamiliar with those and will describe how to do it with control rails instead. I suspect that he can adapt my scheme to the IR gadgets.

Each siding has two control rails, one at each end, and a stop scection with an isolated center rail at the end where the locomotive will stop. The control rail at that end is arranged so that it is bridged before the locomotive stops. The control rail at the other, entrance, end is cleared by the end of the train and not bridged when the train stops.

There are two relays for each siding. The first is an "arming" relay which is operated by the control rail when the train enters the siding. It has a latching contact, which bypasses the control rail to ground when the relay operates. The other contact on the arming relay is in series between the "power" relay's coil and the other control rail. So, if the arming relay is latched by the time the locomotive reaches the end of the siding, the power relay will operate, even though the train is past the first control rail. The power relay controls track power to the stop section of the next train to run.

The other ends of all eight relay coils are connected to the appropriate supply voltage, except that the arming relays' coils are connected through a normally closed contact on a ninth "reset" relay. The reset relay is operated by a control rail somewhere in the section of main line that all the trains pass through.

The two switches for each siding are of the non-derailing type, with the coils within the pair connected together, so that when one switch throws automatically, the other matches it. This way, the switches are always lined to return the train whence it came.

Here is the scenario. A train leaves its siding. As it exits, it throws the trailing-point switch so as not to derail. The corresponding switch at the other end throws at the same time, insuring that the train will be routed back onto the same track. As the train passes the common section of track, it operates the reset relay, which releases all the arming relays. This in turn releases all the power relays.

As the train re-enters its siding, it operates that siding's arming relay, which latches. Then, as it reaches the other end of the siding, it operates the siding's power relay, which has been enabled by the arming relay. This supplies power to the stop section for the next train. An instant later the first train comes fully onto its stop section, and stops. Then the cycle repeats with the second train, and so on.

[Anonymous]

I appreciate the reply. What I hope to do now is to take your written text and turn it into a point to point wiring diagram, then put it all together.

Thanks again.