Layout Intersection - Help!!

[cheech]

The above picture is a small section of a layout i am constructing. It is big for me - 30x24 and there are multiple levels. There is one common to the entire layout.

This part of the layout is a major interesection where four loops cross on 45 degree crossings [Maroon, blue, black and red]. Each loop will be a power division with several power districts [center pin replaced with insulating pins] powered with PoHo via TPCs.  There are 3 leads into yards and sidings [yellow, brown and green] off of switches near this interesection, again each with its separate power [PoHo and  TPC]. Each loop has insulating track in various spots to drive signals. 

I am set to tack it all down and finish wiring connections, but i have a real 'dumb' question.

Will the TMCC stuff --BPC, TPC and PoHo---allow this to be powered separately like i plan or is this setup doomed to fire danger? If i need relays or other power switching devices, could someone suggest some. Any and all advice will be welcome

PS: there is a power bus -12ga 10 colors of wire --that runs around the layout via terminal barrier strips.with feeders to the track about every 6-8 feet.  At each track power connection --by lockon--there is a zenner diode [tvs].  Each power run will have a fast acting fuse between the TPC and the first barrier strip. Accessories, Signals, Lights, Switches are powered separately.

The picture of the entire layout doesn't really fit...i have to work on this. There are a lot of over and ups in the track runs, but the major intersection is in the upper left corner.

 

[eZAK]

Cheech,
It looks like you have one heck of a layout there. A lot of action going on!
You'll need some infared detectors, relays, & insulated track. A BPC or two will help to switch between several TPC's or PH's.
I use all of the above to control a crossover that is fed by several switches.

Good luck!

[TexasEd]

Very ambitious.  I can't help with the wiring, but I would warn about the spacing of the diamonds (crossovers)  you don't want to create a dead spot where the spacing of the diamonds causes both pickup rollers on an engine to be sitting on plastic at the same time.

[chuck]

I don't see any fire danger's per se.  Very ambitous project.  What are the TVS's supposed to do with a clamped spike?  You need to route that power back to someplace "safe" to prevent a dead short that might cause problems for your power supplies.

[cheech]

hi chuck

thanks for taking a look at this project.

in earlier posts, the info i got was

PoHo attd to TPC===> BPC===>Fuse Block===> Power Bus ====>TVS

                                                                                                    ===>Track

the power wires [A and U are my simple terms] from the power bus are each connected to a bi-directional Zenner diode [TVS] and to the lockon at the track.  Did i get it right?

ralph

[MartyE]

Quite a layout there.  The Lionel crosses that you are using can be modified so that the power from one track is separated from the other.  I believe in one of the last CTTs they show this but in case you missed it all it involves is removing the metal plate that joins the four center rails and then using insulated wire to jump across opposite center rails.  As long as you are not looking for collision avoidance I don't see the need for relays.  If you are just looking for isolation between loops using the crosses then modifying the crosses is the way to go. 

 

 

Marty

[chuck]

Marty's points about the isolation of the crossovers is well taken.

Re the Surge Protectors, please refer to this tech article from the Hi Railers web site:

http://www.hirailers.com/technical.htm

A poorly designed or improperly installed unit can cause more problems than it solves.  Looking at the equipment you plan to use, the components have fast action breakers.  If you run only modern equipment, the likelyhood of a surge is much lower than running a mixed environment of Postwar equipment with standard step down transformers and open frame motors.  These devices are more prone to kick off a spike when power is suddenly cut.  Modern switching supplies will usually only spike if the breaker doesn't open in time from a sudden load.  Some of the lower end modern transformers can and will behave badly.  The PowerHouse and TPC are not in that category. 

Use of a device like the ones outlined in the above referenced article or the Lionel TMCC lockon can give you that added protection.

[Birds]

I didn't see if you said you are using tin plate tubular track or not...

If you are using tin plate tubular, here is how I insulated the center rails on my 45 degree crossovers so that I could have two independently controlled loops crossing over it.



I unsoldered the two metal strips and inserted rubber eletrical tape (it is about the thickness of a bicycle inner tube - which would also work well as an insulator) between them.  This separated the metal strips and insulated the center rails so that each part of the crossover can be powered independently.

Enjoy,
Chris

[MartyE]

Chris posted the general idea I was talking about.

[cheech]

Marty/Chris

thanks.....exactly the info i needed to know.  I really appreciate your counsel. 

Chuck

thanks for the info on the TVS.  It was right to point.   I don't think i'll be building the surge protector described in the O Gauger  any time too soon.  It is well beyond my skill level or desire.

I was hoping to run my 1950's PW Canadian Pacific and  SF SuperChief sets on the layout. That's one reason why I went with TPCs.  

I was planning on persuing Scotts Odds & Ends DKT surge suppressor.  Have any of you had experiece with this product. How is it normally grounded? in the outlet?

thanks again

ralph