WIRING PECO SM32 POINTS WHEN USING DCC

TONYWARD50

Tadpole sexing</br>
Yes, I know that you can use the points straight from the box on DCC, and I know that if you have a circuit of track with points or a passing loop that I need to insert insulated rail joiners.
However, the points are self-isolating so if another loco is sat in the loop, or siding, the sound chip will not work until the points are set for that particular loop or siding.
I also know that you can undertake some extra wiring and soldering to make the points permanently live and avoid electrical contact being dependent on just the point blade touching the appropriate rail......
SO..........how do I do this ? The Peco diagram looks more like the electrofrog diagram for OO track, which has slightly different configuration.
Am I going to need to get involved in DPDT switches etc. ? ??? ???
I am running the Accucraft Electric Lew (on 32mm track)which I have just converted to DCC Sound and added a smoke unit. If anyone wants to know how it was done, please let me know.

Yours,
Desperate of Dorset
 
I really didn't want to know a lot of things on this site when they first were posted, but now I quite often find myself searching for bits of information that I now do need and know are lurking somewhere here, so won't you please set out how you did this?
 
To bypass the self-isolating function, surely all you need to do is insert isolating gaps at the ends of the two frog rails, then place jumper wires across from one track to the other so that the trackwork beyond the point is permanently live. It is effectively the same as you would do with a live frog point.

As far as point blade contact is concerned, if you want to remove reliance on this then you need an SPDT switch attached to the tie bar and wired to both of the two closure rails (and the bades), again the same as you would with a live -frog point. It only feeds the blades and short length of track beyond the frog up to where you've installed isolation gaps.

Using an SPDT switch this way means that both blades are at the same polarity, and some DCC users find this gives problems with shorting of blades against the backs of wheel flanges, hence the reason why additional modifications are sometimes recommended to decouple the blades from the closure rails and frog, and to link the blades to their respective main rails. Personally I've not found this to be necessary.
 
Back
Top Bottom