Post by: LanOsb133 on April 27, 2017, 01:07:56 PM
Thanks for any info!
Post by: Alan on April 27, 2017, 01:43:07 PM
Post by: G8B4Life on April 27, 2017, 10:40:54 PM
Without knowing which module standard the club follows I'll make some guesses to what's needed by the module standard they use.
You will need a track bus. It's wired the same for DCC and RailPro, ie probably just two wires with feeders. Being modular it'll have some sort of connector at each end. You can easily add this connector to your RailPro supply for home use.
They may have an accessory bus. This would be the same as for the track bus (except without feeders to the track) and is no different for DCC as for RailPro.
You'll most likely need to include a command/throttle bus and possibly throttle panels on the modules. This wiring has no bearing on RailPro at all but is needed for DCC.
If you follow the wiring standard used by the club for the modules then your modules will work just fine for both DCC and RailPro - as long as you don't try to use a DCC power supply and a RailPro power supply at the same time. The only other thing you'd probably have to worry about is if your modules have turnouts and they are live frog; you'd need to employ some sort of active polarity switching for the frog and not use one of the "auto" types of frog juicers; most don't work on plain DC which will stop you having more fun when running from a RailPro supply.
- Tim
Post by: LanOsb133 on July 06, 2017, 10:10:47 AM
Sadly, you will have to wire for DCC because a DCC booster applies both the motor power and the digital control signal to the rails. Your RP trains will run fine on the DCC wiring.
Well the RailPro power supply won't work for DCC though a DCC supply will work for RailPro so you can't use them at the same time however that has little to do with the actual wiring you need to include on the module. The good news is the difference in wiring for DCC and wiring for RailPro is very little.
Without knowing which module standard the club follows I'll make some guesses to what's needed by the module standard they use.
You will need a track bus. It's wired the same for DCC and RailPro, ie probably just two wires with feeders. Being modular it'll have some sort of connector at each end. You can easily add this connector to your RailPro supply for home use.
They may have an accessory bus. This would be the same as for the track bus (except without feeders to the track) and is no different for DCC as for RailPro.
You'll most likely need to include a command/throttle bus and possibly throttle panels on the modules. This wiring has no bearing on RailPro at all but is needed for DCC.
If you follow the wiring standard used by the club for the modules then your modules will work just fine for both DCC and RailPro - as long as you don't try to use a DCC power supply and a RailPro power supply at the same time. The only other thing you'd probably have to worry about is if your modules have turnouts and they are live frog; you'd need to employ some sort of active polarity switching for the frog and not use one of the "auto" types of frog juicers; most don't work on plain DC which will stop you having more fun when running from a RailPro supply.
- Tim
Thanks for the insight guys, I figured this was the case but wanted to clarify before I started building my little switching modules. Tim so if I wired it all up for DCC, and I was at home, I could still plug in the Rail Pro power supply and power the tracks and than unplug it and take it to the club and have them plug in all the DCC stuff and it should (theoretically) work for them? Given of course that all the wiring is done correctly? I would love to be able to run my modules that way if possible.
Post by: Alan on July 06, 2017, 10:40:59 AM
Quote
I could still plug in the Rail Pro power supply and power the tracks and than unplug it and take it to the club
If I may answer for Tim...
Yes, you can do that. Simply connect the RP power supply to the track bus connector you have for the DCC booster connection. At the club attach their DCC booster, at home attach the RP power supply.
An easy way to think of this is DCC power has two components in series, a power supply and a booster, whereas RP has one, a power supply. Track and layout wiring are the same. If the club uses Loconet you may also need to install a Loconet cable running the length of your modules. It won't actually connect to anything on your modules but it will need to be there to maintain the club's module-to-module Loconet circuit.
Tim makes a very good point about the frogs. DCC juicers don't work on RP DC. To be compatible with both RP and DCC you either go dead frog or use switch motor / manual lever electrical contacts for frog juicing.
A completely different route to go would be to use a complete DCC setup on your modules (minus throttles) and then simply run RP trains on it. The advantage is you can then use DCC frog juicers, auto reversers, occupancy detectors, etcetera for complete interoperability with the club. The obvious disadvantage is cost.
Post by: nodcc4me on July 06, 2017, 12:41:03 PM
Post by: G8B4Life on July 07, 2017, 03:44:02 AM
Thanks for the insight guys, I figured this was the case but wanted to clarify before I started building my little switching modules. Tim so if I wired it all up for DCC, and I was at home, I could still plug in the Rail Pro power supply and power the tracks and than unplug it and take it to the club and have them plug in all the DCC stuff and it should (theoretically) work for them? Given of course that all the wiring is done correctly? I would love to be able to run my modules that way if possible.
Alan has answered this quite well but yes, you will be able to do that. Are the module specs that the club uses online? if they are point us to them and we can ascertain once and for all anything that might throw a spanner in the works.
. . .
Alan brings up an interesting point on powering with DCC at home as well so DCC frog juicers could be used, and I'm just pondering this in my head and not actually suggesting what has been suggested to be a viable solution to any RailPro user that needs dual capability for auto polarity live frogs. I wonder if one could get away with powering with just a booster and not needing a command station for at home use. A second hand booster only for home use would be a lot cheaper than a complete DCC system sans throttles just for powering RailPro at home so DCC frog juicers can be used.
- Tim
Post by: Alan on July 07, 2017, 07:18:52 AM
Quote
booster - command station
Different words for the same thing?
Post by: G8B4Life on July 07, 2017, 07:40:34 AM
Quotebooster - command station
Different words for the same thing?
No they are separate things. A command station can incorporate a booster but a booster cannot incorporate a command station. Let me explain that better.
A command station takes input from devices (usually throttles) and outputs the required DCC packets to the command station output. This command station output is usually "boosted" by an internal booster, but not always.
A booster takes input from the command station output (usually a separate low level line for stand alone boosters but contains the same DCC packets) and amplifies them (boosting) for outputting to the track. A stand alone booster cannot accept throttle input or generate DCC packets by itself.
Stand alone boosters are used to divide a large layout up into power districts and as such there is a need to get the DCC packets from the command station to the districts.
- Tim
Post by: Alan on July 07, 2017, 08:16:33 AM
Post by: G8B4Life on July 07, 2017, 08:52:29 AM
In relation to the OP's question and the suggestion of "using" DCC at home to provide power for RailPro and that we can think of the command station and booster as a single component this is what I'm pondering. A stand alone booster is cheaper than a command station. Since the OP has no need of the command station functionality and it would be a waste of resources (money) to have one just to be able to use things like DCC frog juicers for club use; if a stand alone booster could generate the DCC AC waveform at least without needing command station input then that would be a cheaper avenue than having to get a command station of which he''d only use the power from.
I don't have a stand alone booster so I can't test my theory to prove or disprove it.
Edit: Thinking about this further, if a stand alone booster can't generate the DCC waveform by itself without command station input then the OP could still possibly get by with a stand alone booster and a "DCC waveform generator" for want of a better word to plug into it; not that I know of any DCC waveform generators out there but it could be worth looking into.
- Tim
Post by: Alan on July 07, 2017, 09:28:53 AM
Post by: G8B4Life on July 07, 2017, 11:00:34 AM
A very interesting idea you present there Alan. I'm quite sure all you would need is the raw AC waveform (say all zero's at 100μs); an LM doesn't need the coded waveform and I doubt that non controllable DCC items, like juicers need a coded waveform either. The only thing I can think of that prevents at least me from seeing how pathetically easy this is is don't the rails need to be in opposite phase to each other? I'm sure with a few extra components you could create an opposite phase copy of the darlington pair output but remember, not an electronics genius here.
- Tim
Post by: Alan on July 07, 2017, 11:25:45 AM
And yes, the output transistors would need to be a push-pull configuration.
Post by: G8B4Life on July 07, 2017, 12:03:00 PM
I have sent Tim Ring an email about using a generated raw DCC waveform. Will be interesting to see what he says; probably something about starting a fire ;)
- Tim
Post by: G8B4Life on July 11, 2017, 07:08:27 AM
Because I can't be bothered writing up a story I'll just quote my whole question and RE's answer, without the entire bit on AC and dirty rails which RE put onto the end.
My question, involving shameless plug for RPUG:
Quote
We are having a discussion on the RailPro User group in relation to a member who wishes to build modules for both home and club use. He uses RailPro at home and the club uses DCC. The discussion has centred on that he might have to add DCC specific items to his modules like frog juicers, which we know do not work with RailPro's pure DC.
We also know that an LM can utilise a DCC signal for power. Our question is thus: Does the "DCC signal" that an LM can utilise for power have to be correctly coded DCC packets (0's and 1's) or could the LM utilise a raw DCC waveform (eg, all 0's or all 1's) of the correct duration and amplitude as specified for DCC?
Being able to use a generated raw DCC waveform would allow the member to add club mandated DCC specific items while not having to purchase a DCC system to power RailPro at home.
RE's answer
Quote
As long as the '1's and '0's follow the DCC electrical specification it would not make a difference to the RailPro locomotive modules. However, there are other options than making your own DCC booster. Our AR-1 can be used to power the frogs. You can also use a tortoise or similar slow motion machine and wire the frogs with the extra electrical contacts on the tortoise. We find that insul-frog switches work fine for us and they do not need to do any wiring. If you put a DCC signal on the track it will causes your wheels to get dirty much faster than when running a DC power supply (like our PWR-56). In our testing we have needed to clean DCC powered track 4 times as often as an analog powered track**.
So there we have it, if anyone had any "dumb" (cannot decode the information in the signal) DCC equipment installed on a layout they could build our own DCC waveform generator without the expense of a DCC system for power and off they go. The next question is are DCC frog juicers actually dumb or not?
I took notice of RE's statement that their AR-1 could power frogs. Not sure if he was still talking DCC at that point but I don't think I'd risk it to find out but for DC it's a solution that I didn't think of; though at the cost of an AR-1 I still wouldn't be be using them to auto power frogs.
- Tim
Post by: Alan on July 11, 2017, 08:05:28 AM
The AR-1 definitely will not work with DCC. The input side of the AR-1 is polarity sensitive (marked on the unit and called out on pg3 of manual) so feeding it the DCC AC waveform is out of the question. Plus, as you rightfully mention, it would be a very expensive frog juicer.
The DCC appliances on the market (juicers, occupancy detectors, and the like) are made to work with an AC square wave on the track. Providing the unit is not DCC programmable, there isn't any reason why the duty cycle or pulse width of the AC wave should make any difference. Ironically, it is this square wave that is at the root of the DCC dirty track problem.
Post by: TwinStar on July 11, 2017, 09:59:43 AM