SOLVED** Wiring help, 2 trolleys sharing one line

Some might suggest this is a great Arduino (microcontroller) project but I figure if you're knowledgeable about that method you would have already done it and wouldn't be asking!

The "classic" inner-outer loop with two engines comes up every few years on OGR.  Here's a video of manually controlled operation from this thread. 

In your case, you just draw a vertical line and "cut" this layout in half for out-and-back.

I know I posted a video on a thread on the automated alternating version but I can't seem to find it just now - probably was from before OGR changed to new host so the video and thread are gone. 

The "trick" with the automated version is getting a reliable momentary trigger.   Specifically, after an engine triggers the other side, the trigger must vanish by having that engine mechanically coast past the trigger sensor as power is cut.

Because of bump-and-go reversal, I believe the easiest way to effect a reliable momentary trigger is with timer modules to let a particular trolley exit the siding and go onto the mainline.  In other words, you want the trolley to enter the mainline before "enabling" the trigger that will fire when that trolley returns to the siding...and while one could dream up logic-circuits to do so I think the easiest is to give the trolley 10 or 20 seconds (or whatever) to power up, leave the siding, and enter the mainline.  After this delay, the trigger is enabled so that when the trolley returns it will effect the power switching to the other siding.

As illustrated in the video you can use anti-derailing of the turnout which handles the mechanical steering for "free".

I'd say it can be done for, say, $10 in eBay modules...maybe even without soldering.  No problem to insert a mechanical switch to disable alternating A/B action to operate just A or just B.  It all comes down to your DIY skill/interest.  To pursue further, I'd be interested in your exact configuration - transformer, track type, dimensions, trolley models.  Is this even 3-rail (so that insulated-rail triggering can be used)?  And so on.

I wanted to do this years ago but part of the challenge was how to keep power on the route that was going to be turned off until the trolley "bumped" and reversed.  Relays and some sort of timer I suppose but I gave up in the end.

Thanks Stan, sorry I didn't include more in the post as I was posting from my phone.  A couple additional comments:

• Am running the layout on an old lionel ZW.  Need to get the whistle rectifier upgraded but appears everything else is in working order.
• Running Lionel tubular track
• Trolley line is an out and back, it is about 16 feet long, and uses 2 trestle sets to run up and over the mainline for the rest of the track.
• Will be running a Lionel 060 trolley that my nephew is getting for Christmas, and a 6-8690 that my grandfather bought me 20 years ago.

I'll read through the other thread and see where I can go.  I'm not at all afraid of wiring and trying things.  I spend most my days working on DC systems on Agricultural equipment, but for some reason AC really throws me for a loop doing these things because I'm not as familiar with the components.

JD_Reith posted:

.. I'm not at all afraid of wiring and trying things.  I spend most my days working on DC systems on Agricultural equipment, but for some reason AC really throws me for a loop doing these things because I'm not as familiar with the components.

Not to worry.  What I'm imagining is a DC system (12V) with all the logic, timing, etc. being performed with off-the-shelf 12V DC relay and timer modules.  I was making some chicken-scratches on the proverbial back-of-an-envelope and I'm thinking maybe $10 (free shipping) in eBay modules and parts. 

I'm imagining 6 wires from the track/layout as shown below.  ZW "hot" power would be switched to the A or B sidings which means you would need to isolate power to the two sidings using insulating/fiber pins to create power blocks.  Additionally, within each siding, you would create a section of insulated-outer-rail which would be used for occupancy detection which triggers the swapping of center-rail power to the other side.  A 3-position switch selects A-only, B-only, or alternating A/B operation.  The relay modules would be powered by a 12V DC wall-wart.  I think it can be done with minimal soldering (perhaps just 3 solder connections to the 3-terminal switch).  

The relay modules have screw-terminal inputs and outputs so no soldering required there.  The trick of course is defining the inter-connections between the modules.

The basic idea for automatic alternating operation is as follows.  The mainline is always powered.  Suppose siding A is powered.  Trolley A leaves the siding enters the mainline and when it returns to siding A it trips the A-side isolated-rail and power is swapped from siding A to siding B.  Trolley A stops.  Trolley B starts up.  Trolley B has to run to its bumper, reverse, and then leaving siding B.  This takes, say, 10 seconds.  The "trick" is to disable the siding B occupancy sensor until trolley B has left the siding and has entered the mainline.  That's the purpose of the time delay relay modules which waits, say, 15 seconds before enabling the occupancy sensor on side B.  Non-derailing in the turnout switch will automatically set the turnout direction as trolley B enters the mainline.  When trolley B returns to siding B, the occupancy sensor has now turned on and power is swapped from siding B back to A.  Lather, rinse, repeat.

I figure about $10 out of pocket.  Anyway, does this make any sense at all?  It is somewhat involved and as suggested earlier, is DIY rather than plug-and-play.  I can provide additional details if your eyes haven't glazed over.

Of course if someone else has a simpler solution, let's hear it! 

I think this makes sense to me actually, not sure why I didn’t think about doing it in DC.  The timing relays should work as we intend to always run the trolley line at a fixed voltage  

Im gonna have to try and draw this out tomorrow. One question though, how long of a section of insulated track do you think should be used? Wasn’t sure if it mattered or not. 

You could do it with a lone 2 pos. e unit + 2 isolated rails. You can use what you like really.

  You know some agricultural equip? Relays, saftey loops, etc.. Your general "switching & wiring knowledge" is still pretty applicable.  Mostly; wiring is wiring, (and switches included....: isolated rails are just a funny switch ))

 Staggered movents, but they just sort of "catch up" to the original starting position and continue the cycle from there

  It requires a powered block beyound the stopping block that is long enough for the trolley to reach bump speed from a dead stop; and the isolated rail needs to be centered along each stop block.

A delay is only needed at stops where there is one trolley/siding !

   Where there are two trolleys/2siding at a station, one has been sitting waiting, loading.

  Here's your story, keeping in mind the flow of people is greatest on exit and a good station flows well....      Insufficient funds forbids upgrading the amperage  capability to your traction line and it is only designed to run one trolley at a time, but for station efficiency they use two! For a P.R. spin it is also billed as a conveince and saftey protocal only one trolley moves so a wreck can never happen and you can wait for your departure sitting in the windfree shelter of the trolley cabin.

T-1 arrirves back and t2 leaves immediately. T1 waits for its next departure. t2 come back; unloads. While the platform is full of #2 arrivals, t1 bumps and stops; now staged for departure but waiting breifly for stragglers while t2 bumps and stops now ready to load, so t1 leaves........

With two, 2-siding stations and two 2-position e units, you can run three and they will "juggle" platform postions. 

You might even be able to work this out via the anti derail features on the turnouts.... I'm not awake enough yet..... maybe later...

JD_Reith posted:

.. One question though, how long of a section of insulated track do you think should be used? Wasn’t sure if it mattered or not. 

I may be misunderstanding your question, but in my scheme there are two types of insulation.  First, the center-rails of each siding must be isolated into blocks.  So as shown above, the orange center-rail (A-siding) can be powered/unpowered.  Likewise, the pink center-rail (B siding) can be powered/unpowered.  The mainline red center-rail is always powered.

Additionally, you have the insulated-rail triggers.  There is a lot of flexibility here.  In general, the yellow section only needs to be shorter than the orange section.  It can be just a few inches long or basically long enough so that when the trolley reaches it, the trolley wheel axles will "reliably" short the outer rails to generate the electrical trigger.  As the trolley enters the siding from the mainline, as soon as it hits the insulated rail section (yellow or light blue), it will lose power and coast to a stop...probably in just a few inches but depends of course on initial trolley speed.

In my scheme, when a siding powers up, the trolley must continue to the right, hit the bumper, reverse, start going left and enter the mainline within some number of seconds (say, 10 seconds).  This is where the time-delay comes into play.  The time-delay disables the insulated-rail trigger giving the trolley time to startup, bump-n-reverse, and exit the siding.  You cannot place the leading-edge (left-side) of insulated-rail trigger too close to the bumper or else when you power up a trolley it will not have enough acceleration zone to get up to a fast enough speed to reliably hit the bumper and reverse.  This is probably only about a foot or so but again depends on how much fixed AC track voltage you use.

So here's one way to wire up the contraption using about 10 bucks in eBay relay modules and minimal soldering required.

6 relays are used to perform the logic, sequencing, and power switching.  2 of the 6 relays have time-delay capability. 

As proof of concept, here's a short video showing the automatic switching operation to the shared mainline.  I don't have bump-n-go trolleys so you'll have to use your imagination.  I also don't have the exact relay modules recommended so used 6 relays of an 8-relay module I had.  I also don't have the time-delay relay modules as recommended so there's a bit of circuitry sitting on top of the 8-relay module to add time-delay to 2 of the 8 relays.

I don't know how much "theory of operation" is appropriate but the "trick" if there is one is relays #1 and #2 are wired up to be a latching relay.  One trigger "sets" the relay, a second trigger "resets" the relay.  Yes, one can indeed buy a 12V DC latching relay on eBay with screw-terminals (no soldering required) but it's over $10.  Likewise, one could cobble together latching and timing circuits using digital IC chips which could actually save a couple bucks in out-of-pocket cost, but then this would require wiring up and soldering tiny electronic components.

The other technical tidbit is the positive +12V DC power is tied to the AC outer-rail common.  In other words, when the axle reaches a trigger zone, it provides a +12V DC trigger to the relay circuitry.  This active-high or positive logic makes it easier to work through how the circuit works.

If you locate the trigger zones close enough to the siding bumpers, one could replace the $1.78 60-sec delay relays with 99 cent 10-sec delay relays.

If a trolley can power up, start going toward the bumper, bump-n-reverse, and clear the trigger zone within 10 seconds, then this less expensive delay-relay module could be used.  This goes to the previous comments about where in the siding to locate the insulated-rail trigger zone.

Traditional O22 style switches have this capability built in!

1) Assemble your track. The key here is to add an additional insulating pin on the center rails leaving the straight and curved paths from the switch (but not the base of the "Y").

2) Run track power (say a lockon) to the line at the base of the "Y".

3) On the switch motor, there are 3 terminals - take an end terminal form the switch machine and run it to the center rail of one of the paths leaving the switch. Then do the same for the other terminal and other path leaving the switch.

4) Wire up the O22C switch controller as normal. This can be used to control which trolley line is active.

Purchase Azatrax controllers for a pickle fork or double pickle fork

Thanks guys. Definitely going to get some stuff ordered from Stans idea and will be trying it out after Christmas.  

Nice !! Thanks 

I am still waiting on the last of the supplies to try this out (12 volt wall wart has been slow from China) but am hoping to do the track wiring piece and what I have this weekend.  Worse come to worse I have a 5 amp 12VDC power supply I can use for testing.

One thing I wanted to point out, though from my looking may be a buck or two more but you are starting to be able to get some of the relay modules on Amazon.  So for those of you who have amazon prime already, lot faster way to get these components.

One of my other open projects has been learning Arduino to be able to control an outdoor greenhouse.  It hit me yesterday while working on some logic that arduino would be a very simple way to control what I was looking for, and not that hard to program(yes Stan, I re-read and saw you recommended this up front ).  I am still going to go the simple electrical method as A everything is here but the wall wart, and B once completed this will run at the layout back in Ohio at my dad's and in the long run I see the simple solution being less stress for him to manager (or me to diagnose with him over the phone should something go wrong).  Cost wise also would have been pretty close as the smallest arduino boards can be found for 2-3 bucks and have the inputs needed.  The cool thing about using an arduino that I thought of today was you could actually use the system to calculate and or estimate return time, and then display it on a digital or LCD board as "Trolley departs in XX minutes".  Multiple ways it could be done, could actually calculate the estimated speed, could put some "check" locations on the path, etc.

For those of you reading this still curious about Ardunio but don't want to dig in too deep, easiest way I explained it to a coworker today was that it is a pc board with inputs and outputs that allow you to control items using simple if/and/or logic.  Yes for those who know more about it, it gets much more complicated then this, but it can also just be this simple.

JD_Reith posted:

...I am still going to go the simple electrical method as A everything is here but the wall wart, and B once completed this will run at the layout back in Ohio at my dad's and in the long run I see the simple solution being less stress for him to manager (or me to diagnose with him over the phone should something go wrong). 

Stan,

I‘Ve been trying to get this wired up today but struggling. I think my struggle is from the diagram I don’t see how relay number 3 ever get tripped to switch from NC to NO with the way it is drawn. Perhaps when you added the switch did that cause an error?

Seems to be as drawn relay 3 only gets power when the switch is in the middle off position. So when on the right side on position for alternating trolleys, it never switches from NC to NO to change te powret on the isolated section of the track?

When the 3-position switch is in the upright/center position, nothing is connected to IN3.  This means relay3 is never triggered and hence power is always and only applied to the B siding.  Hence the center-position is referred to as the "B-only" setting.

When the 3-position switch is in the "A-only" setting (which is when the switch is flipped to the right side, then +12V is continuously applied to IN3.  This triggers relay3 all the time.  Hence the A siding is continuously powered.

When the 3-position switch is in the A/B setting (when switch is flipped to the left side), this connects IN3 and IN4 together.  IN4 alternates high (+12V) and low (0V) and of course this is what causes the alternating action.

For troubleshooting, you should be able to flip between A-only and B-only and force relay3 to turn on and off.  Get that confirmed first!

Oh, to be clear, must set the relay module to operate in the "HI" trigger mode which are those push-on jumpers on upper left side of relay board.  Additionally, note that +12V DC from your wall-wart is tied to your outer-rail. 

Thanks Dale, I found out part of my problem yesterday was after two hours of messing with it, I had an idiot moment and completely forgot the switch position is opposite of the connected circuit.  I.E. as you explain when the switch is to the right in the A/B alternate side, you are actually putting out power on the B only middle post through the +12V post on the opposite side.

I've re-verified the switch does as expected, but still ended up with a problem and another question.

Problem: Your drawing shows on the timer relays the connection points attached to the NO part of the relay, but shouldn't the blue wires be attached to the NC?  This appears to be the only way I can get it to work, and in my mind makes some sense as the goal of the timer relay is to allow the trolley to pass back over the trigger point without tripping the relays, so when it goes over the point you want the connection broken which would be NC and not NO?

Question: Through testing with the wiring as stated above, I found that if both the trolleys are in the position where IA/IB is on the rail, that the relays just chatter and constantly switch back and forth.  So my assumption is the trigger point should be short enough the trolley doesn't stop on it, but long enough where it still makes good enough connection to trip the relays?  Also would mean the trigger point needs to be up at the very beginning of the isolated center rail?

Really appreciate all of your help with this!  I'm still not as deep in to Arduino with the greenhouse as I would like to be, but pretty confident now with what I know today I could do this in less time that way.  I've got to say, the relay logic still has me struggling, we don't do anything like this at work, really only use the relays for high amperage connections with low amp triggers.

JD_Reith posted:

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Problem: Your drawing shows on the timer relays the connection points attached to the NO part of the relay, but shouldn't the blue wires be attached to the NC?  This appears to be the only way I can get it to work, and in my mind makes some sense as the goal of the timer relay is to allow the trolley to pass back over the trigger point without tripping the relays, so when it goes over the point you want the connection broken which would be NC and not NO?

The timer-relay modules is a so-called "Delay ON".  In other words, you apply 12V to the inputs on the left, and then after the settable delay interval (say, 10 sec) the relay then turns ON.  The IA and IB "triggers" are connected to the NO contacts because you want the trigger delayed by 10 seconds AFTER power is applied to a siding.  In other words, you want IA and IB to be disabled (or disconnected) to give the trolley time to power up, hit the bumper, cross over the trigger section without causing a trigger, and enter the mainline.  Then after 10 sec, the relay turns ON which enables or connects the trigger section to the circuit when the trolley returns from the mainline.

JD_Reith posted:

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Question: Through testing with the wiring as stated above, I found that if both the trolleys are in the position where IA/IB is on the rail, that the relays just chatter and constantly switch back and forth.  So my assumption is the trigger point should be short enough the trolley doesn't stop on it, but long enough where it still makes good enough connection to trip the relays?  Also would mean the trigger point needs to be up at the very beginning of the isolated center rail?.

Hmm.  Not sure why you're seeing this.  If both A and B trolleys are "permanently" parked on their respective trigger sections, the circuit should simply toggle back and forth at whatever the delay interval is.  So if the Delay-On relays are set to 10 seconds, the power should alternate every 10 sec between the A-siding and the B-siding.  It should not chatter.

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1. Confirm the Delay-On relay module is acting as a Delay-On relay?  In other words you apply 12V to the input on the left, and then it waits 10 sec (or whatever) until the relay then clicks on.  Of course as soon as you remove the 12V at the input, the relay clicks off.

2. Confirm you have +12V from the wall-wart connected to the outer-rail.

3. Confirm you have set all 4 inputs of the 4-relay module for active-hi trigger using the push-on jumpers.

Thanks Stan, I will check more when I get home tonight.  As I had it wired last night it does work with and triggers as I would expect, but only when you don't have the car sitting on the trigger.  I'll note I don't have it wired to track yet, it's still on my bench.

What I do know:

1. Delay-on relay- I'll double check tonight, but from what I did last night this relay when I provide 12 volt power to it, the relay triggers (hear the switch and the LED on it turns green) for the time (roughly 10 seconds I have it set now) and then after that time you hear it click again and the LED indicator turns off.  I checked with my multimeter and was getting continuity between COM and NO while the LED is on, and COM and NC when the LED Is off.  This is the trigger LED, not the power one.

2. 12V+ on outter rail, yes I have it wired this way.

3.  Yes I have all of the triggers on high, never moved them from what it came.

JD_Reith posted:

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1. Delay-on relay- I'll double check tonight, but from what I did last night this relay when I provide 12 volt power to it, the relay triggers (hear the switch and the LED on it turns green) for the time (roughly 10 seconds I have it set now) and then after that time you hear it click again and the LED indicator turns off.  I checked with my multimeter and was getting continuity between COM and NO while the LED is on, and COM and NC when the LED Is off.  This is the trigger LED, not the power one.

If the relay turns ON immediately, I think you're describing a "Delay OFF" relay.  What exact Delay relay do you have?  Some allow you to select DELAY ON or DELAY OFF operation with a simple jumper. 

A Delay ON relay might be used in an automotive application where you the module turns on when you start the car...then after a short delay, the relay turns on applying power to car accessories (so as not to load the battery when starting the car). 

If you indeed have a Delay OFF module, I'd have to think if possible to re-wire to work in the application - could get ugly.

Gentlemen,

   The simple way to run 2 Modern Street Cars is to use 2 PS2 Street Cars on the same track, it works perfectly and eliminates the older type wiring, add some FTCC Switches and have a ball running as many street cars as you desire, with joint MTH and Lionel remote control.

With the new technology why waste time playing the old school game.

PCRR/Dave

Stan,

I purchased the timer relay you referenced in your drawing from what I can tell.  Here is the link timer relay.  On the relay it shows the same labeling as what you drew, looking at the relay left side being where the 12V +/- enters, right side top is NC, middle is COM, right side bottom is NO.  So when you give 12V power to this relay, it switches the relay and you get continuity between COM and NO (center and bottom) for the set time, then it returns to NC.  From your description this would be delay off that is expected correct?  If you think there is potentially something wrong with these relays or have a better recommendation let me know, have no problems ordering more.

Here is the actual relay close-up.  Overall this is what the entire setup looks like bench.

Dave,

I get modern technology and trains would make this simpler, and I could go in to a dissertation of all the reasons why, but the fact of the matter the first trolley was purchased by my grandfather for me, and the second one was purchased by his wife for my nephew.  So these are the two trolleys we will be running 

JD_Reith posted:

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I purchased the timer relay you referenced in your drawing from what I can tell.  Here is the link timer relay.  On the relay it shows the same labeling as what you drew, looking at the relay left side being where the 12V +/- enters, right side top is NC, middle is COM, right side bottom is NO.  So when you give 12V power to this relay, it switches the relay and you get continuity between COM and NO (center and bottom) for the set time, then it returns to NC.  From your description this would be delay off that is expected correct?

Right.  That's behaving as a DELAY OFF relay which is NOT what we want.  Looks like I gave you a bum steer.  Sorry about that.

Kind of annoying though since the listing specifically says DELAY TURN-ON:

In "researching" this more on eBay with other delay relay modules, it appears the wording of this Feature list is copied freely between different relay modules of different behaviors. 

The chattering behavior you describe with both "trolleys" parked on their trigger sections is to be expected if a DELAY OFF relay is used (even if you used COM & NC terminals in an attempt to "reverse" the behavior).  The DELAY OFF relay has a fraction of a second delay when you first apply power on the left-hand terminals before it turns on the relay.  The relay then runs its 10 sec delay and turns off.  The problem is the fraction of a second turn on time is long enough for the parked trolley to trigger and power up the other siding.  The other siding does the same thing.  And they just pass-the-baton back and forth as fast as the relays can turn on and off.

In any case a DELAY ON relay is absolutely required for what I drew. I thought a bit about it and it would be ugly to modify the circuit requiring some resistors and capacitors and some fussing to get the timing right.  Not recommended.

The good news though is I actually have one of those lower-cost 10 sec DELAY ON modules I referenced earlier and I can confirm that it indeed behaves as a DELAY ON module.  I just tested it and it runs up to 14 seconds max delay though it's a sample of 1.  In any event, if 10 seconds is long enough for your trolley to power up, go to the bumper, reverse, and pass over the trigger section (on its way to the mainline), I recommend just getting a pair of these lower cost modules.  I just looked and 99 cent free-shipping is not available just now but several sellers have them for just over a buck free-shipping.

If you need longer delays and want to find another off-the-shelf module, I'd want independent confirmation (maybe someone on youtube showing it in action) that delay-on is indeed delay-on.  Unfortunately we've had this problem before with various low-cost eBay modules from Asia with descriptions that are misleading or simply incorrect.  I should know better by now...

Stan,

Thanks so much for all your help with this project, I finally got the correct delay ON relays in today and it works as intended!  Will be a couple more weeks before I get this installed on the layout, and I've got some more wiring cleanup to do, and some mistake proofing so that when the track crew does the install they can get it right the first time.

I'm positive my niece and nephew are going to love this once it is installed!

Thanks for the progress report!  

I guess once in a blue moon the stars get in alignment!