I finally got a MS2 and start to digitize my layout. I have an 8 ft x 4 ft layout and will run maximum of two locos at the same time. I do have questions for the experts in this forum.

I plan to use my old blue transformers to power the catenary for the analog electric locos since I like the realism of it. I’ll remove the sliders from the electric locos. I also want to power the signals and switches with the blue transformers. Then I’ll use the MS2 and the Switched Mode Power pack to control the ground powered digitized steam and diesel locos.

1) Is this setup workable?
2) If yes, I’ll need to connect the grounds from the two power sources, right?
3) Any suggestion will be appreciated very much.

Thank you for your help.

Hi all!
Why is this not good?

Why can't this be done?
Märklin recommends doing this e.g. when connecting level crossings to digital layouts. This can be done and there is no general problem.


Re 3: The biggest real danger is a connection between the catenary and the centre rail while both are on power. Therefore it is a good idea to remove the slider from all locos fed from catenary.
I'd also recommend to set the transformer to 0 and the MS2 to STOP whenever you fiddle with trains, especially when using tin-plate coaches.
In the worst case you fry the track box 60113. A new track box from a starter set can be bought for EUR 30 or less. With a li'l bit of extra care you won't fry it.


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https://www.marklin-user...igital-Layout#post288234
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Okay, "cannot connect", is better put as "should not connect". Which is closer to what I meant.

I would expect that if you connect the railbox's brown wire to the brown wire from the blue transformer you would create a World of potential problems.

Like e.g. when an analogue old school loco changes direction, or if you some how have a problem with the wiring, or if the loco catenary change-over contact is damaged. You can end up frying the railbox.

There are so many potential problems if you ask me. I just do not think that analogue and digital belong together.

Nope I was not. I know perfectly well that the question came from a three rail user. I was thinking of the spike in voltage that is caused when the blue transformer tells the loco to change direction.

But never mind, I would never do it because of the risks involved. Yes, they are small, but they are there, and if you do not take care, you might end up destroying something. That is basically enough reason for me to not mix analogue and digital.

In scale 1:1 in Germany we have locos that use 16,000 volts at 16.7 cycles per second, street cars that use 800 volts DC, and household voltages with three phases at 230 volts and 50 cycles per second.
And these five voltages share the same ground. The return wire for locos are the rails - and you can touch them at level crossings.

Which negative effects do we expect from 30 volts reversing voltage when we do not see negative effects from 16 volts driving voltage?

Even Märklin write it can be done. And Märklin usually take the safe side with their documents.

Tom, you are correct that when all things are equal and running properly, electrical ground is electrical ground.... but I also have measured the voltage of ground vs the ground on copper water pipes (true ground) and still see low voltage...

It is when not everything is running well or the odd slider touching a rail when the pukos are not high enough or the slider bent, that we may have high voltage hitting ground directly...and working its way back through ground.

New decoders have strong diodes to prevent this but the older decoders, the diodes were weak and could burn out.

My approach to this is have a very simple system and work from there to add on the electrical options. All it takes is a couple of bad wiring connections and you will have electrical problems. I would start with just the track and overhead power and move the switches manually. Once you have good running, then add electric switches. Once that goes well, then add lights....

I have M track and that does not always work well. I heard that others had to electrically isolate the accessories to get mixed power sources to work. I know that the bulbs rely on the ballast for ground.

Hence my earlier comment that yes, it is possible... but be careful. Being careful what to watch for also gives you the ability to determine if is worth attempting this or not based on one's own electrical knowledge and experience, as well as decent troubleshooting skills. I have given some things to watch out for and if these elements are in good order, then the risk of decoder burn out is low.

BTW. On my old M-track layout, I did have separate power supplies. After still getting shocked while cleaning up a nasty derailment that cause rolling stock to get in contact with accessory power (and cause burn marks on a coach under-frame), I rigged up a big power switch that killed all transformers at once.

I run C track now and every accessory is much easily isolated if needed.

OK, glad that you are stating M track. Good track...at least much better than NA track.

I am going off my memory here it has been 6 years since I had my M-track layout (in digital)... to start, do not power the lights yet.

I am definitely sure that they ground out to the ballast. One of my friends did isolate the bulbs to make things more reliable...I think the main issue is this. Bulbs are very crude inductors (vs capacitors that most hear about). If you have enough of them, the digital signal gets distorted and your loks get confused. LED already runs DC and has resistors and diodes to clean the power up before it hits the lights. I only has 4 or so lit switches, so it was OK...I think

I am pretty sure that the switch motor does not ground out to the ballast, but if it does, electrical tape pads will isolate it. It has bee 6 years since I has my M-track layout...I did have separate power for the switch motors (7 of them) with no issues...

Signals are going to be interesting. Those will be track powered but they also stop the + power. Will you use the signals only for digital track power or only for catenary. You can use it for both analogue and digital but you will need the signal to power a double pole, double throw relay or something like that to separate the digital and analogue power.

If you have some electrical skills, go step by step, working with your least valuable loks to get it working and then trying more valuable loks before going on to the next step.

Again, the issue with bulbs and switch motors. A few items can be tolerated by the digital system to have common ground....at least at the track level. Once the level of inductance gets beyond a certain point, problems start to occur. (Coils cause inductance, and you have a big coil in the switch motor and a tiny one in the bulb).

Hi All,

I have done this before long ago when I first started getting back into this hobby of ours.

Connecting the two "Browns" is not a problem (in Fact I had problems when I did not do this recently).

I used a simple on-off-on toggle switch to make sure the two "red" signal never meet. I used only M-track and no catanary to do this at the time.

The obvious problem was that I was never able to run in both modes at the same time.

I must stress that I used the more modern light blue transformers and not he older dark blue ones.

hopes this helps.


Enjoy

Leon