Hi,

Short answer is "no", you cannot run a 3 rail loco on 2 rail system, and 3 rail locos are not easy to convert to 2 rail either. But depending on the decoder specs (others will clarify this I guess) you can use your existing DCC controller on your 3 rail layout. I would consider this as an exciting step into the world of HO and 3 rail.

If you have more questions, just fire away.

Cem.

So, the short answer is "no"

He's asking if you can run a 3 rail loco on a 2 rail system, not if you can run it with DCC

To carify: you can run any loco in any digital language as long as the decoder in loco speaks the same language.

C.

Sure thing.

Well, it is not different from 2 rail, the only difference is that while you have (-) and (+) connected to the two rails you have in 2 rail system, you connect the (+) to the center rail and (-) to both rails on the sides (I mean the two regular rails) in 3 rail system. That's all to the wiring.

C.

Hello, that is a nice looking Marklin "Bavarian Freight Train" Train Set you have bought. I cannot comment on the Z21 controller, because I have never used it. I hope the other people have answered that particular question for you.

As for the track, you will need Marklin 3 rail track. Marklin trains are only compatible with Marklin track. Marklin has made three different types of 3 rail HO gauge tracks, thru the years. They are called the ”M”, ”C” and ”K” tracks. M track is the oldest, not being made anymore. But it was made for over many years, from 1935 until around 2001. So there is a lot available on the used second hand market. M track is a metal roadbed base. From 1935 until the middle 1950's, M track had a solid third rail down the middle. From the middle 1950's until production stopped around 2001, the "center rail" were stud contacts.

In 1969 Märklin introduced the “K-track” system, which had plastic sleepers (ties) and no attached roadbed. And it also contains the stud contacts down the center of the track. K track is meant to be used with wood, cork or foam roadbed. Marklin still produces K track today. It is the only Marklin track line that offers flex-track.

Then the C track was introduced in 1996, (which had it's beginnings in 1988 (the Alpha train). C track contains a plastic molded roadbed. And it also contains the stud contacts down the center of the track.

All Marklin track produced since the middle 1950's (until today), has studs located in the center of the track. All Marklin locomotives need a 3rd rail collector to collect the electricity from the stud contacts. They are also called a pickup shoe slider.

To operate your Marklin train, you will need Marklin track. The choice is yours, you can use any Marklin track, of the C, K and C types. Whatever you like and prefer, they all work fine with Marklin trains. Because your Marklin Bavarian Freight Train is highly detailed and realistic looking, I would recommend the Marklin K or C track. Both are more realistic looking, compared to vintage M track. Some people like to use only one type of track (M, or K or C). While some people use a mixture of all of them, with the proper adapter track pieces, that Marklin also makes.

Marklin trains will not work on 2 rail track, they are designed for 3 rail track.

Other brands of locomotives will not work on Marklin track, unless those locomotives have been purposely designed to run on Marklin track from the factory. Or they have been modified by someone, that added a pickup shoe slider to their locomotive, and modified anything else as needed.

Generally speaking, you run 3 rail Marklin trains on 3 rail Marklin track. And you keep 2 rail trains, on 2 rail track.

Unless you are very experienced in modifying things.

Hope that helps.

You can connect just like you connect your Z21 to your 2 rail system assuming that it already has a transformer (seperate or integrated). Just check the output voltage of your Z21, it should be 18V DC. AFAIK all digital systems are 18V or thereabouts, but I stand corrected.

As per tracks; C is the most convenient type, many here use C, I've converted to C some time ago from M.

Cem.

NO NO NO !!! The Z21 is completely capable of controlling this train set !!!

It has absolutely nothing to do with AC or if it's 3-rail !!!

PeFu gave a perfect and correct answer



I really wish you would stop telling people this nonsense about AC and DC; there's no AC anywhere in this "Maerklin train package"

The correct is this:

You bought a Maerklin train package which always requires 3 rail tracks. If you would have run it on your 2 rail tracks, than you should have bought this train set in N gauge from Trix and not from Maerklin. Trix is the brand from Maerklin for 2 rail tracks. But both train sets understand the track formats DCC and MM (= Maerklin Motorola). Meanwhile the MM track format is extended to mfx. Maerklin is ( now?? ) offering only locos for 3 rail tracks with mfx decoders.

You've been told hundreds of times......................

Per.

sorry wrong, even the old 6021 can use all functions on this locomotive. activating secondary, 3rd and 4th addresses. Since I don’t have a z21 I cant say for sure that it would work, but I would be surprised if it don’t.

If you get some Märklin K track, and modify the turnouts and feeder track you can use the same track for 2 rail trains as well, But not at the same time. read more here: https://www.marklin-users.net/forum/posts/t12817-DC-on-Marklin-K-track

If you are building a layout, Peco might be an alternative. (using https://peco-uk.com/products/stud-contact-strip-for-track )
but its fiddley work and I don’t really recommend it. have done it on a small layout.

Your wording of "always requires AC" is wrong. If you would have said "always requires a 3 rail system" you would have been more correct.

A digital system, as you yourself point out is neither AC or DC, therefore, your "always requires AC" is wrong.

Peter

Below is the diagram showing track voltage details on Marklin digital 3-rail system, and DCC 2-rail system. Both Marklin digital and DCC actually output AC signal to the track, the voltage swing from positive to negative. In digital system, the difference in track voltage will not be a problem as long as not exceeding the maximum voltage of the decoder.



below is the diagram showing track voltage of Marklin analog and digital system.

The track voltage on Marklin digital is indeed AC signal.
It swing from +18V toward -18V (peak-to-peak voltage is 36V). And yes, the direction of electron flow is switched back and forth. You can measure (and see the waveform) on an oscilloscope.
The difference to Marklin AC analog, beside the voltage, is the waveform of the signal and frequency. Marklin AC analog is sinusoidal at constant frequency (50Hz or 60Hz) while Marklin digital is square wave and variable frequency (modulated by the protocol).

No, it's an alternating DC signal

To be considered AC it has to be periodically, otherwise none of the formulas for calculating AC
current or voltage can be used

Period .

Per.

I agree

If just people not knowing the difference between 2-rail systems, 3-rail systems, AC, DC and digital signals would stop writing
all their long misleading posts, we wouldn't have these discussions again and again

Per.

Exactly, please let us stick to industry noms and not pursue abstract theoretical justifications about why a bipolar variable frequency square wave signal can be called AC. This does not help Mr. Joe Average, nor does it enhance a reputation.

I'm going to be naughty here.....

How come I need to have my multimeter set to the 'AC' setting to be able to measure the voltage.....?

It's probably better to describe it for what it is - more or less a square wave - fast rise time, then a DC bit, then fast (whatever it is called) back to zero.

Depending on the quality of multimeter, you'll get very different readings, and since your multimeter
probably doesn't have a "digital signal" setting, you have to use the closest available

Try to set your multimeter to DC voltage, and you'll still be able to measure "something";
this "something" is actually the proof that the digital signal isn't a symmetrical and/or periodically AC

Basically everything related to AC can be calculated using "Euler's formula";
if you try to do that with a digital signal you will get wrong results

https://en.wikipedia.org/wiki/Euler%27s_formula

If you're interested, read also this about Euler's formula; it's been called both "most beautiful theorem in mathematics",
the "greatest equation ever" and "of exquisite beauty"

https://en.wikipedia.org/wiki/Euler%27s_identity

Per.

Ajith, to make things simple. Your digital control box has two cables, one red and one brown, that you use to connect to the tracks, correct?
To connect them to the Maerklin tracks the red cable goes to the contact marked 'B', under the track bed, and the brown cable goes to the 'O' contact.
The rest does not count, AC/DC is a heavy metal rock band. Enjoy :-)

The Fluke reads a couple of volts, when I've done this by mistake.

Dear All,

I just wanted to add few things.

First of all thank you for the response, you all are great !!

I am also an engineer, electronics and communication ! So would like to add few things down here!

DCC - Digital Command and Control, used for model railroading carried two ‘elements’. One the necessary power to drive the loco and second is the digital signal for the processor inside the loco to do different functions. It also carries addresses to each loco with loco specific commands. These functions are from speed of the loco to triggering different sounds etc

What is shown in the oscilloscope is a digital signal. What you are seeing is the digital signal which is carrying all the information required for the decoder.

This DCC is DC ! The whole world of ‘digital electrics’ is based on DC. I understand my statement, so lets not start another argument on this. There is also ‘power electronics’ which has AC in it


And I believe, I might be wrong here so I leave others to commend. The current and voltage of DCC remains same and it is the driver inside the loco controls the current or voltage going to the loco motor to change the speed. I am not sure the motors are constant current driven or voltage driven.

It is wrong and misleading for Reynolds to put their 3 rail Marklin locos with an ‘AC’ symbol. This is where things went out of control in our discussions.

Z21 can be used to control Marklin 3 rail locos like any DCC system, only thing I need to do is, change the signal / power feed from 2 rail system to 3 rail system. In 3 rail system, both the rails are getting same signal and the contact in the middle carries the second lead / signal.

Yes, may be some functions of marlin mfx+ digital decoder can’t be activated. But I feel if Z21 wants, they could just make an update to address that. More on that, others in the group could add.

Thank you every one !

More time with your locos as some of you may be on a "home quarantine as a precautionary measure", like me :)

Stay positive and happy rail roading. May be this ‘down time’ from office could be used to learn new things

Cheers from Dubai.

Ajith

I've locked this topic as the original question has been answered, and we seem to have had since then more than enough silly nonsense to last a lifetime posted.