Block Management (Design)

[peach james]

I think this topic should be pulled from TTG's RR&Co bit, as it holds more relevence than just to RR&Co.

 

There are several ways to design the lengths of Detection Sections (DS) required for automation. The important things to think of is where would the train stop? At the point where you want trains to stop, you need to have a way of identifying that.

 

Some software allows for the use of interpolation of train position based on speed. (RR&Co 5.0 and up). This will allow for the use of less DS for a similar effect. I would recommend against relying on this as an absolute position unless the same loco is working the same train, or if some variance in position is acceptable.

 

If you are going to automate, consider where you need to know position before you do substatial wiring.

 

Further entries welcome as to how other people size them, and I will add some more,

 

James

[two tone green]

Before going any further with this, have you looked at RR&Co V7 Gold and the ability of it to have multiple stopping positions in a block using only one block occupancy detecter.

[peach james]

It would come down to how close is close enough ?

 

If every time, you want the same position, then you probably should have a DS to allow for accurate location. If it is a most of the time thing, then again, it probably would be a logical position to cut one. If it is a once in a while, then the use of the distance from the last DS change is acceptable.

 

If you are like John, and trying to acchieve mm precision, then the use of the same loco, stock, and program are all going to be required. Even then, I would expect the occasional rough shunt...

 

Even though RR&Co 7.0 Gold allows you to reduce the # of DS used, it doesn't mean you of necessity want to. I am well aware of the limits of 5.0 and previous, in that I am going to have issues with locations of signals not exactly corrisponding to the start of the next DS. In 5.0, this is going to cause me grief- I know !. I understand that it would cause me less grief had I had some idea where I needed to have DS's prior to wiring-that ~6" before each home (stop) signal would be ideal for absolute block purposes. I'm still suspicious that I will end up going back and redoing a moderate amount of my wiring at some point to acchieve that. (and that is the point behind this thread, to give some ideas where the ends of DS's should be, and a way of asking if enough or too many are being planned...)

 

James

[Andy LMRG]

Again I may be a bit late here, having only just realised that the "old" web is replaced by this new one. We have tried all sorts of ways of trying to achieve precision. One factor that has caught us out is temperature. As an example the Hornby Class 156 00 guage unit is REALLY sluggish until the railway room warms up whereas the Bachmann Class 4T romps away at almost the same speed whatever the temperature. (You may wonder what a Class 156 and a 4MT are doing on the same layout - don't ask!). As a result the more you "estimate" or "interpolate" stopping points from the last known detection section, the more variable the stopping point. ALL our experience says detect where you want to stop and even then to stop smoothly and accurately means really setting up decoder CVs accurately and ensuring the section used to detect the stopping point is long enough when trains are warm!