Two Simultaneous Lionel O trains using two CW-80's??

[grandpa rich]

I have resurrected two 1950's Lionel 3-track O gauge trains (2 engines and a few cars each) on a track system composed of an inner loop and an outer loop connected via 4 manual switches. I purchased ONE Lionel CW-80 transformer and had hoped it would be powerful enough to run both trains simultaneously, but it simply doesn't supply enough power, and both trains slow down to a crawl, or stop altogether. In my olden daze, with old transformers now gone, I simply ran my two old transformers wired in parallel to power my two-train system. If I purchase a second CW-80, can I sucessfully wire them in the same way? I just gave my 6-year-old grandson my entire set, and of course, he is thrilled. But we are disappointed that the one CW-80 can only power one train at a time, and I told him I would find out if grandpa Rich can come up with a solution.

To clarify/expand my earlier version of this posting, all I want to do is run one train in the inner loop of track and simultaneously run the second train in the outer loop. Historically, there was no independent control of each train, and I don't need that now. I simply had both trains running simultaneously at whatever speed each was driven by the combined throttle setting of the two combined-in-parallel transformers. To stop, or reverse, the trains, I simply turned off the transformers momentarily. To exchange which train is running on which loop, I simply manually flipped the track switches at an appropriate time where each train could switch tracks without running into the other.

So, will a 2nd CW-80 wired in parallel do the job? We are not looking for anything more complicated, or versatile, at the moment. I am a little concerned that these more modern Lionel CW-80's might automatically shut down or something if I connect them in parallel like I did in the good ol' days.

I am sure you experienced conductors realize that we cannot power one track loop with one transformer and the other loop separately with the other transformer because, when one of the trains enters the same loop as the second train during the transition switching (lasts for a few seconds), then a single transformer would be powering both trains, and the single CW-80 will power down.

 

[LoudMusic]

I think what you'll want to do is create electrical blocks of track. This will allow you to choose which controller is controlling each block of track with a toggle switch. Usually this involves an A / B / Off switch for each section of track you wish to be independantly controllable. I had such a setup on an HO layout with two 4x8 sheets of plywood and it works marvelously.

There are controllers that have two throttles for this very purpose. I believe Lionel actually made one, but I am not for certain. MRC, http://www.modelrectifier.com/ , makes several models for DC operation of two trains, and I've never heard a bad word spoken about their products.

 

[grandpa rich]

Thanks for your very quick reply. I have tried to clarify my question and desire a little more by revising my original posting some. I really don't wish to INDEPENDENTLY control the two trains. I merely wish to simultaneously drive both trains around their respective inner or outer loop, and switch them between loops as described in my edited posting.

 

[60103]

Rich: the CW80 has some wierd electronics in it. The feeling at the Classic Toy Trains board is that it was wired backwards. It's also a bit underpowered -- it may do for one train if you don't add too much load to it.
If you're going for a second transformer, I would suggest that you separate the loops (fiber pins in the crossovers) and run them independently.

 

[grandpa rich]

Thanks again Loud Music and Pooh Bah, but my question is more simple than your very thoughtful answers.

I simply want to know, is there someone out there who knows for sure, will two CW-80s hooked up in parallel actually serve as a more powerful single transformer to run my two trains the way I want to? (Please read the details of my original question).

I realize there will be two throttles to deal with in this effectively 160 watt transformer, but that worked for me just fine many years ago with earlier transformers.

 

[pgandw]

As David said, the CW-80 electronically simulates a traditional transformer. Given the variety of problems folks on other forums have posted with using just one CW-80, I would be rather reluctant to tell you that you can successfully parallel two of them. There is really no way to guess how the electronics will react to the situation.

Even paralleling 2 post war traditional transformers was/is asking for trouble. Since it is impossible to match the output voltages exactly, there is a "fault" current that flows from one transformer to the other that is proportional to the difference in output voltages. Your transformer circuit breaker does NOT protect against this fault current. Although the older transformers were rugged pieces of iron, I have heard of the sliding contactor and transformer windings burning where a fault current was allowed to exist for prolonged periods.

Correctly phasing transformers is necessary to keep the voltage differences small. If transformers are out of phase, the voltage difference is the SUM of the output voltage of the 2 transformers. This will create a large fault current if the 2 transformers are connected together. The CW-80 cannot be phased because its internal electronics produce a chopped wave of varying phase rather than a true sine wave.

The traditional way to wire your situation is to isolate the 2 loops from each other. It's very simple, just put insulating pins in the center rails where the 2 loops connect. Then each transformer controls its own loop. Usually the transformers are phased so that the voltage differences and fault currents that occur when the center pickups on a loco bridge the insulating pins are minimized.

What LoudMusic suggested is a more elegant method that further minimizes fault currents and provides for greater flexibility in control.

While this is long-winded, my intent is to explain why certain ideas work well and others don't.

my thoughts, your choices

 

[grandpa rich]

THANKS FOR THE "TWO CW-80's IN PARALLEL" INFO!! A NEW QUESTION.

:thumb: Thank you so much all three of you who responded to my querry. Thanks especially to Fred Wright for his self-claimed "long-winded" discussion, for he provided the additional clear insight I needed to fully understand why the other responses were so useful. By the way, Fred, your comments joggled my foggy memory that, while I had remembered the joy and success I had as a child using 2 transformers in parallel to create the power I needed, your warnings then reminded me that, after some years of success, both transformers burned out...the coil in one and the slider in the other! Thought you might enjoy confirmation of your wisdom. I certainly did. I WILL NOT BE BUYING A SECOND CW-80 AND LIKELY DESTROYING IT WHEN I TRIED TO PARALLEL IT WITH ANOTHER.

While the suggestions of David and Loud Music could most likely be implemented if I were next to my grandson to help him carry them out, I am afraid I have left him with a setup that most easily benefits from a single 160 watt or more transformer.

ops: SO, COULD SOMEONE WITH GOOD EXPERIENCE PLEASE ADVISE ME WHERE/HOW TO OBTAIN A REASONABLY-PRICED SINGLE-THROTTLE 160 WATT OR MORE TRANSFORMER FOR LIONEL TRAINS THAT WOULD HAVE THE DESIRABLE WHISTLE-BUTTON LIKE THE CW-80???

 

[cidchase]

Pardon me fer bein' ignorant, but if it takes 80 watts to run one of these trains,
would Lionel build a single-control 160 watt transformer??
There are several KW's offered on ebay, some with guarantees.

 

[pgandw]

Pardon me fer bein' ignorant, but if it takes 80 watts to run one of these trains,
would Lionel build a single-control 160 watt transformer??
There are several KW's offered on ebay, some with guarantees.

I second the suggestion - a used KW would power both trains adequately, and was designed for the '50s era trains. Each of the two throttles on the KW has its own whistle/horn controller. Unless you have a long train of lighted passenger cars, neither train should be drawing more than about 45-60 watts (3-4 amps). If the locos are really drawing more than that, I would clean and relube.

And please put insulating pins in the center rail where the 2 loops join, and wire a loop to each throttle.

Finally, an alternative to the KW is two 1033 or 1044 transformers - one for each loop.

my thoughts, your choices

 

[grandpa rich]

Thanks one more time; just one more puzzle.

Thanks Cid and, once again, Fred Wright. I have ordered a refurbished KW (190 watt) as you both suggested, and am having it sent in time for Xmas to my grandson's parents (my daughter and her husband). There should be many years of excitement and joy for all, thanks to your sage guidance!!

For no real intentional act on my part, I did notice, when setting up the track system for my grandson, that the Lionel manual switches placed all four as close together as possible seemed to accomplish on their own the electrical isolation of the central rail between the inner loop and outer loop of track. So it seems I may be ok without any further isolation pins as you suggest.

One puzzle does remain for me, however, and that puzzle was part of my original posting.

It was posted as an assumed statement of fact, rather than as a question, when I wrote orignally the following: "I am sure you experienced conductors realize that we cannot power one track loop with one transformer and the other loop separately with the other transformer because, when one of the trains enters the same loop as the second train during the transition switching (lasts for a few seconds), then a single transformer would be powering both trains, and the single CW-80 will power down."

This statement was certainly true for my experience with a single CW-80. SO, BY THE SAME LOGIC WITH THE KW TRANSFORMER, WON'T THE ONE HALF OF THE KW TRANSFORMER BE OVER-LOADED, AND SLOW THE TRAINS INTOLERABLY DOWN (OR SHUT DOWN THE TRANSFORMER ALTOGETHER) DURING THE SHORT TIME WHERE JUST ONE HALF OF THE TRANSFORMER IS POWERING BOTH TRAINS ON A SINGLE LOOP???

 

[60103]

grandpa: I won't comment on the last bit as I don't entirely understand the electrics.
Lionel made some manual switches (I had a pair) with a "non-derailing" feature which cut power to the center rail when it was thrown the other way. This could be isolating your two loops, but they will be connected when you set the switch for crossing. Further situation: setting all 4 switches for the crossover may isolate bits of the layout depending on where the feeders are.

 

[pgandw]

Grandpa

To answer your last question first: The 2 throttles of the KW use the same primary winding. Each tap (throttle) draws what it needs. The combined total cannot exceed the output rating of the transformer - about 140 watts/10 amps for a KW - but each throttle can draw up to that much individually. Older Lionel transformers were rated by input, not output. Output ratings have been required since the 1980s.

David is right. Certain 027 manual switches (and perhaps O or Super O manual switches?) killed power to the center rail to prevent a train running a switch thrown against it. This means your loops will be isolated when the switches are thrown for the loop. But when you throw the switches for the crossover, you will cross-connect the 2 throttles, creating the fault current I described in the earlier post. Please, put an insulating pin in the middle rail between the 2 loops at all connections for the long term good of your transformer. Then the only time a fault current will flow is when the rollers of an engine span the insulating pin, which should be for very brief periods of time.

To avoid the fault issue almost completely, you need to go to block control. But I sense you are not ready for block control at this time. Again, please put in the insulated pins in the center rails between the loop connections for the present.

 

[grandpa rich]

Thanks To Fred Wright & Friends For Their Keen Advice!!

announce1 And one final time on this issue, thanks again Fred Wright for your clear and complete expertise. I very much have enjoyed being on your "track" while you tutored me on the finer points of model railroading. You and all others have been so very helpful in answering my questions.

Your can be assured, Fred, I will install the insulating pins as you advise.

Yes, you are right, I looked very carefully into Loud Music's clever suggestion of blocks of track, and felt it would be fun for me if I were controlling the trains to control the transformers and blocks of track as he suggested. But, my going-on-6-year-old grandson would be a little overwhelmed at this point if I implemented such additional complexity to his already challenging track layout I have created for him (and left for him to operate on his own).

THANKS, AGAIN, ALL YOU GUYS. I HAVE LEARNED AND BENEFITTED A LOT FROM THIS FORUM AND YOUR KIND REPLYS TO MY QUESTIONS.