Seen this before? MTH LED Full Vista Dome 20-64071

@VThokie Steam Fan posted:

Actually I was looking at using the Accessory Output from my Z4000 ( 10VAC or 14VAC) to power Menards Buildings and other LED lights on the layout.

Understood.  There have been several OGR threads on this.  You can get low-voltage AC-to-DC converter modules such as:

The above unit even has screw-terminals which might make hookup easier (rather than having to solder).

There are some power issues to consider when applying these converters (total Amps or Watts) for building lighting.  Menards buildings are all over the map on their power requirements as I think the smallest has only 2 LEDs while some of the larger buildings have hundreds of LEDs!  You really need to do the math!  Rather than muddy the waters for your Vista Dome modification, I'm pretty sure a simple OGR search will pull up several relevant threads.

Sounds good! Thanks John and Stan! I will post once I have the Vista Dome apart and have pictures. With a 2.5 year old and the wife 35 weeks pregnant, projects do not move as fast, but hopefully I will have some pictures soon.

@gunrunnerjohn posted:

No way that's going to happen Stan, I think with 55 VAC on the rails, you'd not have to worry about lighting the cars!

Same comment, 55 VAC is the minimum input voltage.

I was coming at it from another angle.  That is, for AC-to-DC conversion in rolling stock the low-voltage module I posted above works fine at 18V AC input...converts to 5V DC, 12V DC, or whatever DC voltage as needed in the rolling stock.  But that module is $3 or more and arguably a bit bulky...and still requires the DCS 22uH inductor, and, and, and...

It is also a non-isolated converter where the DC output "minus" cannot be tied to the chassis/frame which is typically electrically connected to outer-rail AC common.  This can have implications in some rolling stock applications.  Hence, I was curious if the isolated feature of the 55V AC converter was the basis for the question.

And, I suspect for every low-voltage AC-to-DC converter module made, a million or more 120V AC  converter module are made which goes to cost.  There would/could be a separate discussion on how to modify an inexpensive 55V AC converter to operate at 18V AC.  But I see that is not the issue...

First Step Done. Removed Main Shell. Here is the bottom floor of the car

Top Board Pictures: Board is flush so you cannot place anything but wires behind it.

I removed the capacitor and soldered in wire leads to relocate the capacitor to the end of the car where there is room to hide it.

AND The best part!!! MTH Installed a Choke at the input power leads:

Looks like you got the job done.

@gunrunnerjohn posted:

Yep Stan, the good ol' days are gone, I see very few of those kinds of listings now.  I was thinking about that when I was digging out more 1N4007 diodes from my pack of 1,000 I bought years ago, still working my way through them.  I think I paid less than $4 for the diodes at the time, less than half a cent each.

I did get a recent bargain on eBay, and when I looked again, I see that they made a mistake in the listing, for a change in my favor.

I bought three of these, for a total of $4.80, I thought a pretty good deal.

When I go to the current listing, it obviously was a pretty good deal!  Now they're four times the price!

GRJ, This caught my attention.  Is this what I think it is:  a device to drop a 110 volt accessory down to a 5 volt dc accessory that you can then attach to a 5 volt power source?  I have a 110 volt used accessory that I'd like to make this conversion:

@IRON HORSE posted:

GRJ, This caught my attention.  Is this what I think it is:  a device to drop a 110 volt accessory down to a 5 volt dc accessory that you can then attach to a 5 volt power source?  I have a 110 volt used accessory that I'd like to make this conversion:

Yep, that's exactly what it is.  Obviously, you need to put it into a proper enclosure as it's running 110 volts on the primary of the transformer!  It claims 600ma, but I suspect 200-300ma is closer to what I'd expect to be able to draw from it.

eBay: 373578134151 has them for $1.66 shipped free.  I also notice they reduced the power output claims to 300ma, more along the lines I was thinking would be the capability of this board.

Thanks, John.  Excellent information on an already great topic here!

@IRON HORSE posted:

GRJ, This caught my attention.  Is this what I think it is:  a device to drop a 110 volt accessory down to a 5 volt dc accessory that you can then attach to a 5 volt power source?  I have a 110 volt used accessory that I'd like to make this conversion:

Not sure I understand you project.  Is the 110V AC from the white 2-prong cord going into the paver?  Doesn't that mean there's a 110V AC motor (or whatever) inside the paver?  Is the project then to convert the 110V AC motor to a 5V DC motor and then change the power to 5V DC?

In any case, be sure you have enough power.  Not sure what your accessory actually does and hence how much power (in Watts) is required.  If the eBay converter is indeed "only" 200-300mA, then at 5V it is providing between 1.0 and 1.5 Watts. 

Note that these inexpensive DIY converters are what you would find inside the ubiquitious 5V chargers used for smartphones, tablets, and the like that charge via a micro-USB connector. 

Depending on your wiring, you might be able to use some part of a generic charger like this to get your 5V DC from 110V AC.

Great photos.  So it appears that in this style passenger car, MTH does the AC-to-DC conversion as one would expect on the lower board (with DCS choke...albeit apparently an after-thought since it's not on the board).  Then, DC is passed to the upper board via the pair of spring contacts.  That is, the upper board does not have diodes installed so it is operating on DC.  While mission-accomplished here, the DC interface between lower and upper might be used to advantage in a different project.

Stan, there is a motor inside the wood housing that the cord connects to.  I was hoping I could use a step down device and cut the plug off to connect to a 5volt or 12 volt dc power source.  It's sounds like there might indeed not be enough power to operate the 110 volt motor, huh?   --Mike

Must be a senior moment, but I'm still having a problem understanding the problem!

What exactly does the accessory do?!   

Your picture shows what appears to be a so-called AC synchronous gearmotor.  These are inexpensive 110V AC power motors that have a gear reduction mechanism so it rotates very slowly.  The $2 Amazon gear motor spins about 6 RPM when powered by AC line voltage... or one revolution every 10 seconds...very slow.  And it only consumes about 4 Watts.

This particular style of motor will NOT rotate if 5V or 12V DC is applied to it.  It would just get hot!

Of course you could replace the 110V/120V AC synchronous gear motor with a low-voltage (5V, 12V, whatever) DC gear motor.  Obviously this requires fussing with the mechanical coupling from the DC gear motor to whatever shaft connection is made from the paver to the existing AC motor...often it's a so-called D-shaft because the shaft looks like a D rather than a round O.  If you want to pursue this, I suggest starting another thread in the Electrical Forum and I will throw in my 2 cents.

Stan, You are not having a senior moment.  You understood the problem fine.  Thanks for your time and input.  You saved me a lot of time and frustration.