Will it be DCC?

Probably too obvious, but if DCC, maybe keep-alives would work for you? I use the TCS KA2 and they can run my O scale locos with sound and LED lights for between about 2 and 6 seconds, depending on Atlas or Pittman motors. Plenty enough to get over dead frogs, might not be enough if the whole turnout is un-powered though. 

https://www.tcsdcc.com/Customer_Content/Products/Keep-Alive/Keep-Alive.php

Power Long Enough?

The biggest problem I see using keep-alive modules would be if the loco happens to stop on the unpowered turnout (probably very likely during switching operations).  You would obviously need more than a few seconds of power if you wanted assurance that the loco would again move when you opened the throttle.

Here is a thread that covered

Here is a thread that covered just that: http://model-railroad-hobbyist.com/node/22134

It is wireless DCC using the Tam Valley Depot system.

I hope it helps.

Regards, Volker
Germany

dead section

If the loco stops in a dead section no amount of battery or capacitor storage is going to start it again. It won't be receiving any commands if it gets them via the track.

For my money the ideal is direct radio control using the DCC protocol with a small battery constantly charged from the track using the batteries of my choice. No wiring of points required, no charging routines and the track/wheels will not need to to be surgically clean to work reliably.

Unless you are running small 2 or 3 axle switchers, a twin truck diesel normally works reliably without the frog wired providing all wheels are picking up (as they should). Steamers with pickup on loco and tender are just as reliable.

regards

Bob

"using keep-alive modules"  

I was thinking that using supplemental batteries would let me eliminate all turnout wiring while keep alive caps would just allow unpowered frogs but still need some turnout wiring. Installing a  small battery seems like a good trade off for not needing to wire anything but the flextrack lengths of the layout. As for the DCC or not question;  I don't think it matters on this layout, any locos will just run here and I don't mind having a different control system if it makes the wiring and operating problems easier. I think the main thing to consider is a seamless transition between track and battery power, size of components, and easy and reliability of installation, if DCC makes these things easier then fine, if something else would then that's fine too......DaveB

DCC or not

The question is: Do you want to have sound? Than you need DCC or RailPro. For DCC the Tam Valley Depot or Stanton S-Cab systems offer a direct wireless connection to DCC (sound)-decoders. NCE offers a dead rail decoder  (non-sound) with on-board receiver for Tam Valley, S-Cab, and others:
https://ncedcc.zendesk.com/hc/en-us/articles/201713349-D13DRJ-Dead-Rail-Decoder

If you don't need sound the Deltang R/C system might be an alternative. It works on 2.4 GHz and the receiver has an on-board speed controller. Using track power requires a bridge rectifier and buffer capacitors or batteries. Without backup power the receiver would shut down when the pick-up is interrupted:
http://www.deltang.co.uk/trains.htm 

Here is an address to buy Deltang in the USA: http://on30guy.gerenm.net/shop/
/> The website is better organized than Deltang's and information is easier accessible.

I'm considering a similar way but have not decided yet. I'm running SP steam locomotives and a number have Vanderbilt Tenders. The brass tenders a soldered up like a tin and I hesitate to cut the painted tenders open. So I'm looking for a solution that fits into the cab and boiler. The Deltang receivers are small enough but the rest?

Regards, Volker
Germany

Battery Power

I would look at as "battery power, with charging from the rails", vs "powered from the rails with battery assistance"

A control System like Railpro, which communicates directly with the locomotives not through the rail, could easily be run from a battery. A small charging circuit would see that the batteries were topped up whenever it was on the powered rails. The battery would not have to be very large for this paradigm.

"A control System like

    Hi Bill, That's what I was thinking. Railpro seems to discourage battery use on their website so I'm not sure what battery/rail power interfaced would work with it.   Stanton seems to have what I want but their production seems very limited, I don't know anyone who has one of their systems.  I don't know if the Stanton battery/rail power board would work with Rail pro, perhaps someone has figured out how to use Rail pro this way? .....DaveB 

Railpro seems to discourage battery use on their website

This is because if the voltage drops too low you'll have frustration, but if the voltage is kept above 14 volts there will be no problems.

I think the biggest issue would be when you are programming the loco, if it lost power during a file write, that could be bad, so you'd want to make sure you're not on "only" battery power then.

The other issue that is going to prevent Ring from fully endorsing battery power is this: if you lost signal for some reason while the train was in motion, if it is battery powered, how do you stop it?  With Railpro, you can turn off the controller and leave the loco doing what it was doing. Turning the controller back on regains control. This allows intermittent loss of signal without having trains ground to a halt, allows for out of range etc.  If you're on track power and you loose control, you can just cut the power. On battery, you could run off the end of the layout.

I doubt there will ever be an official endorsement of battery power from Ring.  That said, I think a keep alive technology is in the works.

The loss of R/C signal is a

The loss of R/C signal is a problem that all dead rail systems have I think. DCC decoders, RailPro decoders, and even Deltang receivers have a number of light outputs one can use to disconnect the battery.

If you read the RailPro FAQs there is no real no there:
http://www.ringengineering.com/RailProFrequentlyAskedQuestions.htm#BatteryPoweredLongAnswer

It is more like it is not needed with DC track power and the batteries are currently not good enough etc..

At the end they write: If battery technology gets to the point where we believe the majority of users would benefit from it we would develop battery packs to be used with RailPro locomotive modules.  And the good news is that every RailPro locomotive module we have sold in the past can be battery powered by simply wiring an appropriate battery to the existing power input of the locomotive module.

Using battery power means you have to use a battery pack with high enough voltage or a single battery with an appropriate  step-down circuit for loading and step-up circuit to provide power to the decoder. But that is not just for RailPro.

Regards, Volker
Germany

Battery as keep alive

The idea of using a battery, like a capacitor, is worthwhile depending on the battery type. My Li-ion are sensitive to charging. The chargers sense heat and taper or shut down the charge but are relatively small and can be built into the system if you are interested in charging from the rails. Most "dead rail" guys, myself included, don't want power on the rails other than that for detection. Small batteries like those used in pens or headsets will be 3.7 volts but can stepped up to 12V with converters made by Sparkfun or Pololu Electronics. 

Have fun!

Neil

About Stanton

Bernard K has written some post here:

http://usmrr.blogspot.no/search/label/DCC

Charging from rails

Dear MRHers,

My understanding RE charging from rails is:

- Charging LiPos (Properly/reliably/over-long-term-operations) from the rails is hard,
due to the need to balance multi-cell LiPos during charge/discharge.

- TVD get around this by not trying to charge from rails,
instead obliging the use of a proper "LiPo multi-cell charger unit" external to the loco. 

PROs:
* Simple
* Cheap (IE the TVD circuit does not need to have a battery manager/tamer/charger circuit built-in saving $$$ and space)
* Battery format is logical to the modeller
(I have a 12V motored loco, so I need a 12V capable (multi-cell) LiPo battery).

CONs:
* need to take the loco apart to access the multi-tap battery connections, in order to charge
(Yet to see a "real world deployed" external charging jack system, visually defensible or not, 
with multi-pin connection for proper charging of multi-cell batteries).

- S-Cab tackle the issue head-on by using a single-cell LiPo (3.7V), avoiding the use of multi-cell LiPos from the outset. (a single-cell LiPo does not have the "multi cell management headaches" of a multi-cell battery).

"...but but but, how does an S-Cab run 12V motored locos off a 3.7V battery?"

The answer is a dedicated battery manager/tamer/charger circuit which
(somehow, I'm not 100% clear on the method of operations)
amplifies the 3.7V up to around 12V.

PROs:
* simpler for the modeller (just place the loco on almost any form of powered track, and it's charging)
* no need to tear apart locos or host visually indefensible charging jacks on the loco exterior

CONs:
* more circuitry to fit inside an already cramped loco shell
(battery circuit possibly offset by space-saving use of a smaller single-cell battery?)

Personally, I struggle to get past the "I have a ready-made pair of buss-bars that my loco is always riding on, why not use them?"
(If the loco is not touching the rails, the loco has Derailed, and you have bigger issues to deal with...)

but if I felt the need to go "battery-powered", charging from the rails would be hogh on my personal list of priorities...
(I've said it before, the TVD "familiar DCC system > DeadRail Radio Tx" transmitter/adaptor + S-Cab "charge from rails DCC+Sound" combo is about as close as current tech gets to my personally preferred solution).

Happy Modelling,
Aim to Improve,
Prof Klyzlr

" the TVD "familiar DCC

Hi Prof, I thought so too but I'm wondering why it's not in more widespread use? I don't know if it's a lack of production bottle neck or a problem with the system in the real world? I guess my second best solution would be wire up most of the turnout rails and let a keep alive cap take care of the dead frogs? It would be nice though to just wire the plain track and stop the wiring when a turnout or group of turnouts is reached :> ) .....DaveB 

Off Track Charging or UPS

Intermittent Charging

Using LiPos and many other battery technologies in an active charging system can get complicated very fast, and the reason that they are seldom used in uninterrupted power supplies (UPS). Balancing is one problem but integrated circuits and boards are available so this not a big problem. Most of these technologies are only good for a limited number or charge cycles and even short charging cycles count for some technologies. So charging the battery every time you hit a hot section of track could add up charging cycles very fast, but there are also smart battery integrated circuits which attempt to control when a battery is charged. However, even with these devices using LiPo and similar technologies in an intermittent charging application can really reduce battery reliability.

Single Cell Option

As I noted on the other thread I installed the S-CAB receiver in one locomotive with the Battery Power Supply (BPS). Although it works, the effective energy density with the BPS was less that that available with a multi cell installation. I have also run a Tam Valley Dead Rail System (DRS) receiver with a BPS with similar results. Note: The use of a BPS, which is a step-up or boost switching power supply, still requires an external charger. An internal, off track charging circuit could be added to the BPS, but that would result in a much large board and still have to deal with the intermittent charging issue.

Actually Working in Large Scale

I currently have more than six battery capable Large Scale locomotives / systems which I regularly run and which are setup to allow charging from the rails. I have used the locomotive / system terminology because most of these units can be switched to run off of rail, battery and or battery plus track power. Several of the battery systems are installed freight or passenger cars which can be connected to the almost any properly wired locomotive (Like most AristoCraft locomotives). Some of these locomotives have DCC decoders, some have QSI decoders with receivers and some have Crest Revolution receivers. With the intermittent, repetitive charging LiPo's have proven less reliable than NiCads, but I am currently running the significantly more expensive LiFePO4 which are currently holding up much better.

Early next year I will be installing some of the DRS1 Hi Power up to 28 Volts 5 Amp receivers to test in the garden.

I was working on an off track battery charging circuit with balancing  (Mini-UPS Controller) which would have been about the size of the BPS (could be installed in an HO trailing battery car), but the manufacturer of the primary chip pulled the design. Hopefully they, or another manufacturer, will release a redesigned chip in the near future.

S-CAB and DRS Users

We actually have several S-CAB and DRS users in the area (they had seen my HO installs), but they are not forum addicts users, so you will not find them in these discussions. Most are very satisfied with their operation with the biggest issue being lace of space for installation.

BPS contains battery charger

Quote Ken: The use of a BPS, which is a step-up or boost switching power supply, still requires an external charger. An internal, off track charging circuit could be added to the BPS, but that would result in a much large board..

The S-Cab BPS contains a charger and a step-up circuit.

Quote from http://www.s-cab.com/battery-power.html

Battery charging
External power supply for battery charging connects to terminals labeled “IN” (the gray wires). Just about any voltage supply greater than 6 volts can be used; DC, AC or DCC. If track has power connected, the battery charges whenever BPS circuit senses track voltage.

Regards, Volker
Germany

so....

BPS + BPS Battery + Railpro and you're wireless & deadrail in an HO loco with charging from track power. 

add Power Trucks and you're wireless in a small HO loco.

cool!

Of course you could use the S-Cab too   But RailPro is so simple to use!

 "would result in a much

I guess there's more to this problem than I first thought. Perhaps I should first try a keep alive cap or Wow decoder and just wire up more of the rails? .......DaveB 

Worth a try to wire turnouts imho

I wire my turnouts "DCC friendly" with gapped frogs, feeders to stock rails jumpered to closure rail and closure rail wired to switch point with flexible wire. Diverging rails receive power from the next feeder or are jumpered. Most turnouts have Tortoise-switched powered frogs.

But in my yard, the frogs aren't all powered due to old Atlas switches with pot-metal frogs. Since I added keep-alives, I have no more stalling, light flickering or sound drop-outs running down my 6-switch ladder. I know it's a pain to have to wire up each switch in 3-4 places, but I do think it's worth it, and it can be done after installation easy enough.

If you can stand doing that, then I think you can operate DCC with keep-alives without powered frogs and have no issues.

If I were starting over now, I would definitely look at dead-rail battery as I have lots of room in O scale locos. But I'm 20 years into DCC so keep-alives are my salvation!

I do use graphite very sparingly on all rails and that helped a lot with locos where I don't ye have keep-alives. 

Pete  

BPS Charging and Track Power

Volker, You are correct. Sorry I was not clear that I was referring to the Dead Rail application. Bad Day at the Salt Mine. The BPS's work well in track powered installations, but you are still limited in power density in most HO installations.

 "But RailPro is so simple to

Hi Bill,  Yeah I'd definitely consider Railpro if I was planning to MU lots of locos but this layout is a shortline that had just a few locos and only occasionally MU 'd them so I'm not sure I'd get full benefit from it.  Now that I've heard about the power/battery toggling with possible charging cycle troubles I'm leaning toward trying a test of the Wow decoders over dead frogs and see if that is adequate for the needs.That alone would simplify the wiring quite a bit and eliminate the need for tortoise or frog juicers.......DaveB