Conversion of 3 track O gauge to DC

[daan]

A link to their website: http://www.spur0shop.de/55501.html It seems to be a stepdown convertor from 220 to 110 volts with a frequency converter built in. It deliveres 110 volts 60Hz AC on the output!!

Someone discovered a gap in the market!!

[lionelsoni]

I'm a little put off by the roughness of that machine.  It looks like it might be a homemade DC supply, perhaps around 12 volts, that may be available at the banana jacks on the front and also fed to a separate slicker-looking inverter tucked underneath.  If that really puts out only 110 volts, it's fine for prewar transformers, but a little marginal for the modern 120-volt stuff that might really need the 60 hertz.

[Anonymous]

Hi everyone! I'd like to start by saying thanks. What a great Forum, I never expected as many replies or as much detailed info.

I decided to go for it tonight and convert to DC. The main reason for this is that because my wife runs a Thomas the tank engine shop, and we want to import these sets, we really needed a good solution which allows us to provide a UK spec tested and stamped UK power supply. I know some european dealers supply converters or 18v AC supplies but as we only want to import Lionel Thomas and Percy, a lot of the accessories ( horns etc )are not too much of a loss.

I opened up Percy and reconnected the Black and red from the chassis straight into the black and red for the motor. The two orange feeds were removed and both circuit boards discarded. Initially I tried a Lionel G scale controller for DC from a Bachmann HO powerpack.  Brilliant! I can't get over how smooth Percy runs even at very low speeds. The horn switch now works as a cut off/isolation switch. The horn has also gone. The motor must have been DC to start with as I now have control of direction using the normal switch on the controller ie reversing the polarity.

I have just finished for the night having modified Thomas in the same way. Also much smoother.

I have no idea why they seem so much quieter or go faster (almost exactly twice the speed). As Lionel seem to rectify within the loco and then feed a normal DC motor perhaps they only rectify one side of the AC? I don't know enough to be sure but after running them for over 3hours together there seems to be no problems. I had an unmodified Percy as a comparison re speed.

On a side note they do both seem sensitive to dirty track, tripping out the power supply for fractions of a second if they loose contact. The Bachmann supply is for HO Digital and although bigger than the HO DC one is maybe not getting enough current to the controller.

I will measure the current load tommorrow and see if I need a bigger Supply. Perhaps an LGB G scale one?

All in all it seems to have worked. Thanks again for all the help everyone, and I can definitely agree with brianel027 about the smoothness. I'd love to know why though.....

 Anyway I will post again about the current load.

 Thanks again!

Kenny

[lionelsoni]

The MTH electronic reversing units that I have reverse-engineered include not only the rectifier diodes but also several additional diodes in series with the motors.  I think that this is an attempt to loose much of the 5 volts that conventional transformers start out at.  So, when you connect the motors directly to a DC supply, it is reasonable that you get a response from the motors at a much lower voltage.

You might want to research the convention that Lionel used for their DC locomotives, that is, what direction they go for what voltage polarity.  If you ever had a customer already using the old Lionel convention, it would be nice if the new locomotives worked the same way.  Perhaps someone on the forum knows which way they go and we can get the answer easily.

[daan]

In the MTH protosound 1 units, the light is a constant 5 volt print. The lights are working on 5 volt, no matter how fast you drive the train. I guess that's why the rectifiers are in front of the motors, otherwise the train would start to run without lights. Also I guess the relais in the e-unit (on trainsound units) needs a certain voltage to work.

If converting into DC you can get sound by adding a european Lenz type decoder (in AC it would be a märklin decoder, I've thought of that option too). You'll be able to switch the lights, sounds and everything using a Lenz digital or Märklin systems controller. They are powerfull enough (up to 5 amps) to control a 0 gauge locomotive and available in europe.

But for me, the most obvious thing was to preorder a convertor (even more because of an MTH Z750 in the mail) and make the trains run on 60Hz AC..