Wiring Question

[Anonymous]

Hello all,

I received my MRC Prodigy Express today and am looking forward to getting home and playing with it. However, I have a question. My son has a Thomas engine that I do not anticipate putting a decoder in so I planned on having a toggle switch to choose between DC and DCC. No problem. However, in looking in my decoder manual, it suggests that I build a TEST track to test decoder installation. My thought was to purchase a DPDT On-On-On switch that would allow me to have three positions, 1 for DCC, 1 for DC, and 1 for the test track. The programming track, obviously, has its own lugs on the DCC system, so it would be separate.

Having said all of that, how do I wire this up? Any websites that might help me out?

Thanks,
Darrin

[BR60103]

Darrin: doesn't sound like what I'd try.
Your test track should have direct wiring from the DCC power pack. Yu might want to ignore it for DC operation.
You could use a DPDT to switch the rest of the layout between DC and DCC. You can run a DC loco on DCC as #00, but it's a bit noisy and controversial.
I think most DCC locos will run on RC -- switching an entire layout over would have your sone running all your locos as well.
Other warning: do not allow the DC and DCC power supplies to mix -- dire consequences for one of the power supplies.
You should consider chipping the Thomas with the cheapest chip available. You can always recover it later if you need to.

[rrinker]

There's no real reason to have a seperate test track, except maybe in a club situation where some peopel might want to work on decoder installations and test them without distrubing other members who are running trains on the layout.
What you SHOULD have though is a seperate programming track - I believe the PE has a dedicated programming track output. Maybe not. And what you should do after installing a new decoder is to put the loco on the programming track - NOT the layout - the programming track is current limited and if you made a wiring mistake it won't destroy the decoder. Try programming the new decoder, at least with an address. If it works, then you have a good chance of having everything wired correctly and it should run on the layout just fine. If it does not program, don't put it on the main track until you figure out why
This goes for ANY DCC system that supports a dedicated programming track.

--Randy

[Anonymous]

Thanks guys!
Randy, I wondered about that. So the Test track that is mentioned in the decoder instructions is only there for those systems that don't have a programming track?! That makes a lot of sense. I just couldn't fathom having to have a programming track AND a test track. Didn't compute for me.

David, I had thought of that, but I haven't looked inside Thomas to see how much space there is. Now that I have a decoder in hand, I'll have to do that and see if it is feasible.

Thanks again.

Darrin

[rrinker]

Well, depending on if there is a programming track or not, you can wire things slightly differently. WITH a programming track output, you can double gap the end of a siding and feed it with a DPDT switch. the CENTER of the switch goes to the track, one side goes to the program output and the other side goes to the regular track output. Flip the switch one way, it's a programming track, the other way, a regular track you can use. WITHOUT a program track output, you should feed the isolated part directly from the track output, and the entire rest of the layout through a DPST (or just use one side of a DPDT, they're more common). When you want to program, turn OFF the rest of the layout - since anything on the track in such a system will be programmed. By isolating the rest of the layout, the only thing that would get programmed is whatever is on the isolated siding.

--Randy

[Anonymous]

Excellent info Randy. The PE does have a programming track output, so I'm good to go there.

I did notice a rather odd thing last night and maybe somebody here can help me. I managed to install a decoder in the one locomotive I have that seemed like isolating the motor was pretty straightforward, and it was. I got everything all soldered up and hooke the Prodigy Express to the programming track, had the Pilot light lit and went to access Locomotive #3, the default for the decoder, and got nothing.

I inspected all connections to make sure that I didn't cross a wire or anything. Made sure I had good connectivity to the track. Everything looked good, so I tried again. Nothing. Since everything looked good, I threw caution to the wind and decided to try it on the main. So, I switched the wiring around (since this is still on my workbench and I haven't added the PE to the temporary layout yet) and was able to operate the locomotive successfully.

My question is this: Does there have to be a circuit on the main connection in order for the programming track connection to work? Once I got the locomotive to operate, I was satisfied that I had the decoder installed correctly, so I switched the wires back to the test track and still got nothing. I didn't, however, connect a track to the main and to the programming connections, but don't know how that would make a difference.

Any suggestions?

Thanks again,
Darrin

[bandmjim]

Not positive on this but think you might be ok, as many program track outputs are lower power, I had a Prodigy system and think, if I remember correctly, that you should notice the light function, and a slight movement of the loco upon programing it. It probably won't take off running like on your main track. Think your manual will mention this.?
Jim

[Modeloldtimer]

You can access the loco #03 while the locomotive is on the programing Track. DO your programing while the engine is on on the programing track. You can change the decodrer's address to to match the number of engine etc. Once the decoder address AD2=03 is changed to say AD2=05. Place the loco on the main or switch track power from program mode to main or test track mode. DO not have the Programing track and any other track connected together at any time. Dial up or select the new engine's address. The engine will answer to the new number 5 or the number that you programed the decoder to.
To set the decoder's address AD2=( X ) - Note ( X ) is any two diget number ) TO set a decoder to a 4 diget address use AD4 EXample. AD4=1234 which 1234 are the numbers you chose for the four digit Address AD4=1234 Locomotive #1234 is controled.

[Anonymous]

That's the interesting thing. I was able, with the locomotive on the programming track and connection, to change the address from 03 to 04, but it still did not respond to any other input at all. No light, no motion, nothing. I'll play with it more and see if I can figure out what the problem is. I was pretty tired.

Thanks again for all of the great input.

[BR60103]

I think if it's set for programming, you can't actually run the loco. Not sure, but I seem to remember that the loco jerks a little when the programmer finds the address, but then nothing.
The controller should have output for the programming track and a different output for the main layout.

[aggiewonder]

QUOTE: Originally posted by BigDarrin

Thanks guys!
Randy, I wondered about that. So the Test track that is mentioned in the decoder instructions is only there for those systems that don't have a programming track?! That makes a lot of sense. I just couldn't fathom having to have a programming track AND a test track. Didn't compute for me.

David, I had thought of that, but I haven't looked inside Thomas to see how much space there is. Now that I have a decoder in hand, I'll have to do that and see if it is feasible.

Thanks again.

Darrin

Darrin:

Here's a link you might find interesting regarding the Thomas engine and a decoder installation:

http://www.trainbuddy.com/Reference/Decoding%20Engines/thomas.htm

Hope this helps...I'll be doing this once I get my RR up and running DCC...will have to "convert" Percy as well...