Convert to DCC

[ColinB]

I agree with howbiman, soldering a socket makes things so much easier. On a Bachmann A4, I recently converted (it was the split chassis one) there was no room to fit the 8 pin socket, so I fitted a 6 pin one. The big plus point is it easily gives you the chance to recheck that it still works on DC, by just changing the header, you also easily change decoder makes, if one doesn't work very well. I don't have a Select but I have an Elite and I have found that all the decoders I have tried with it always work. The issues I have had is when you want to change CV values or set a new address or read values, with certain decoders this does not always work reliably. So a ZTC decoder should work.

[Rog RJ]

As resetting hasn't worked and ZTC decoders can be strange beasts, try writing 6 to CV 29 and then write 3 to CV 1 to return to default address 3.

[Mist22]

Thanks to  howbinman and to Colin for their suggesions. Rog I'm afraid altering CV29 hasn't solved the problem although the motor showed very slight signs of activity but very short lived. I've tested the motor separately from the controller and without the decoder and it runs easily. Do you think there is any possibility that the power supply (I have the 1A supply) is insufficient to power the motor fitted. to an older Hornby Prarie loco (6147) which was later converted to DCC? 

[ColinB]

You didn't mention that, that might be the case. I don't know the current limit for a ZTC decoder, but I think they have decent current limiting, so rather than blowing up, which has happened to me on a number of occasions with old locos, it is probably just limiting the current which would mean the loco doesn't work properly. Try fitting a Zimo, Train o Matic or some other make with a higher current limit. Avoid Hornby ones for old locos, because they have a current limit of about 0.5 of an amp, which is ok for their modern locos, but not high enough for any of their older locos. Even some of the 0-4-0 Hornby locos draw more than 0.5 of an amp, although some people on this site get the Hornby decoder to work, but why take the chance when a higher spec decoder is virtually the same price.

That is why I always fit a socket, it makes changing the decoder so much easier. If you can't get an 8 pin one to fit, use a 6 pin one. If you do fit a 6 pin socket use the DCC concepts one, they seem to be a bit more robust. On the cheaper ones it is so easy to pull the the pin out of the socket or break the wire off. The DCC concepts ones go to a PCB which makes them less likely to do that and easier to fix it if it does.

[Fishmanoz]

There is some confusion here. Colin is answering whether an 8249 has sufficient current capability to run the loco, not whether the 1 Amp PSU for the Select will provide enough power, that being the question asked immediately above.

 

Checking out service sheet 238 for the Prairie, it has a can motor so chances are it draws less than 500mA.  However, this should be confirmed with a DC stall test, or Colin's preferred measurement of the armature resistance. 

On the current (pun intended) question above, the 1 Amp Select PSU should be sufficient to run a single loco and, if not, the Select should trip out on overload.  That said, the 4 Amp PSU is known to solve a number of problems with the Select so would be a good investment. Especially if wanting to run more than one older loco.

[ColinB]

If it is the same "can" motor that is fitted into a 0-4-0 or GW panier 0-6-0, I found that their current consumption was very variable. One I tested drew more than 500 mA another one less. I know RAF96 is running one with a Hornby decoder, but when I did a "stall test" on one of mine it was drawing way above 500 mA, although I did replace that one for a better one I had.