Powerfeeds to the tracks!

[Henri]

Is it a good idea to have more than one power feed to the tracks? As 'garden works' are in the planning the next couple of weeks, I just as well might drop in some tubing for power wires...

What is advised as the interval in meters between two feeds?

 

[Neil Robinson]

Is it a good idea to have more than one power feed to the tracks? As 'garden works' are in the planning the next couple of weeks, I just as well might drop in some tubing for power wires...

What is advised as the interval in meters between two feeds?

Opinions differ on this.
Mine is that the rail will be much thicker than wire so, provided joints are kept clean and tight, one good feed is enough.

 

[sparky230]

I use multiple feeds, not for power reasons as the track is thicker than the wire, but for fail safe reasons, ie broken joints etc
My layout is split into blocks for operational reasons, with a short isolated section between blocks, every block has 2 power feeds, one at begining of block and one at end of block, ie either side of the isolated section, each isolated section is wired back to a set of overide switches, so it can become a complete loop if I want.

 

[James Day]

Sparky,

Your layout sounds a lot like mine! I too have three separately powered sections, fed at each end. I use an LGB double isolating rail as the boundary between each section and feed through the terminals on either side.

Very large gauge wire is used for the feeds. Each is linked through a 5amp control hut and then back to a 5amp Gaugemaster 22v transformer inside the garage. I have a meter bank in the garage to show what power is being used and all the supplies pass through a 'panic box' which is in a waterproof container outside. This has a large red button to sever all the supplies if everything goes horribly wrong, although it rarely does.

James

 

[stockers]

Probably a good idea to have more than one connection to the track. On a simple layout, perhaps a feed to the closest part of the layout and then take it onward, straight across to the other side. Any wire will do but it is probably worth using a relatively thick core as some trains can pull a fair amount of power. Probably not too much of a problem now but you will probably expand it. I use redundant mains cable - just make sure it wont get mixed up with the real stuff!

 

[sparky230]

Sparky,

Your layout sounds a lot like mine! I too have three separately powered sections, fed at each end. I use an LGB double isolating rail as the boundary between each section and feed through the terminals on either side.

Very large gauge wire is used for the feeds. Each is linked through a 5amp control hut and then back to a 5amp Gaugemaster 22v transformer inside the garage. I have a meter bank in the garage to show what power is being used and all the supplies pass through a 'panic box' which is in a waterproof container outside. This has a large red button to sever all the supplies if everything goes horribly wrong, although it rarely does.

James

4 block sections, with automatic holding/passing loop in station, based on EPL diagrams but using double coil relays instead of EPL drives, originaly built with EPL drives but replaced with double coil relays for reliability, my isolating sections are just made by cutting track and using massoth insulated clamps, which also provide the track feed points. Use industrial PMR power controllers and a 15 amp industrial switch mode power supply at 20v

 

[stockers]

Sounds a bit complicated for a beginner though!

 

[Henri]

Haha! I just will post more questions, so...

 

[James Day]

4 block sections, with automatic holding/passing loop in station, based on EPL diagrams but using double coil relays instead of EPL drives, originaly built with EPL drives but replaced with double coil relays for reliability, my isolating sections are just made by cutting track and using massoth insulated clamps, which also provide the track feed points. Use industrial PMR power controllers and a 15 amp industrial switch mode power supply at 20v

That is impressive indeed.

My mainline is divided into seven automated block sections, and four lapping loops. All using EPL parts including timers and signals made from combining Playmobil colour light signals with the original type of EPL add on switches. To add interest there are two catenary equipped branches where up to five trains can run - two of them passing each other half way along, before crossing the main line at a junction with a custom made logic box. This takes inputs from EPL reeds and that controls the junction signals. These are also interlocked with the block signalling on the main line.

Operation is mainly automated and the trains run quite happily from one of the three seperately powered sections into the next without issues.

James

 

[Henri]

You flip the switch, grab a glass of beer/wine and that's it?

 

[sparky230]

Thats about it, 2 150ft loops, each loop runs 4 trains at, time, 1 in station, 3 on blocks, you need one more block than locos for it work, one loco drives into main station, another goes out, blocks are either stations, or sensible halt postions, 2 Colour LED signals, Magnets on bottom on locos. Use PWM on the controller as allows almost full line voltage to the 18v smoke stacks, no loco has any fancy electronics

 

[James Day]

Sparky has said it.

Put them on the track and off they go. Loads of colour and movement and always stopping and starting in different combinations of action.

Beer in hand -Yes please!

James

 

[Martino]

I'm running DCC and have about 400' of track. Two reverse loops and a branch.

I have two feeds, one at each end. Works pretty well.

 

[Greg Elmassian]

I have DCC, and do run trains that draw up to 10 amps.

I have stainless steel rail and stainless steel clamps (split jaw) at all locations

I have sectional track, so more joints.

I run large (10 gauge) feeders about every 30-40 feet.

Why? because I measured the voltage drop ACROSS ONE JOINER and it was significant.... rail joiners, no matter how clean still have some resistance.

Now why can some people feed a large layout in 2 places, and a guy like me needs 30-40 feet for each feed?

Simple, how much current are you drawing, and how much is lost through joiners... remember Ohms law: V=IR

OK the "R" is the resistance through a joiner. It should be clear that V (the voltage drop, i.e. "lost") is directly proportional to the current drawn.

So, high current trains, lots of joiners, and how much voltage drop you can tolerate all factor in.

I recommend overbuilding the supply wiring, this is often convenient when the layout is being built and very inconvenient later, so get it right the first time.

Greg

 

[sparky230]

I will admit my layout might be overkill on joints as they are all soldered apart from the massoth insulated clamps and the track clamps on station turnouts, Being a spark and radio ham, I figured in Ohms law and soldered the joints.

 

[Greg Elmassian]

That's actually the best option!

73 de N6RGZ

 

[Madman]

I will admit my layout might be overkill on joints as they are all soldered apart from the massoth insulated clamps and the track clamps on station turnouts, Being a spark and radio ham, I figured in Ohms law and soldered the joints.

That's how I handled my track when I ran track power. Simply the best, by far, solution, and the most labor intensive.....

 

[sparky230]

That's actually the best option!

73 de N6RGZ

de 2E0IJH (144mhz op G3WM/p)

 

[Rhinochugger]

On my old layout, I had about 180 feet of track, mostly Aristo with screwed fishplate joints, so I introduced a second feed about midway.

Both track feeds were 6.5 mm2 cable (I had a sparky do the calcs for me to obviate voltage drop on the supply cables) and thus was borne the cooker cable club - with a membership of one so far

This all came about from my days maintaining airfield ground lighting, where the voltage is deliberately reduced in stages along the runway to ensure the lights all have the same intensity. Thus as the voltage is reduced, the transformers increase the amperage, so you can get killed with 24v on AGL (which is why on MoD siites you need a permit to work signed of by an Authorised Person). It's surprising what garbage you can remember, when you can't remember the name of a bloke you talked to last week

 

[stockers]

6.5mm2. I think you may be on for a record there mate. And I'll bet voltage drop is not an issue!