I'm a newbie doing a small 2x4 N scale layout and was wondering about the general consensus regarding the inclusion of an insulated programming track segment or not when one has another DCC base station, if needed, to perform service mode programming? Are there particular reasons to have an insulated programming track on layout? Pros and cons?
Pro would be it is very easy to do with a single toggle switch, DPDT. Doing it on a siding would mean that you would not be reprogrammed any locos that are on the rest of the layout. If you only had one local at a time on the layout then you could just use the layout. DCC++ Ex with a raspberry pi with JMRI on it would give you a complete DCC layout with a dedicated computer running JMRI and phone throttles for under $100. Sumner
Thank you for the info.... Actually, using DCC++ EX and going to add Pi for JMRI although if the wiThrottle server in DCC++ EX had a way to push out Function button labels without JMRI, don't think would even need JMRI and PI on the layout? love DCC++ EX and have multiple Arduino's and Shields so why have a programming track?? When service mode programming is required, figured on doing it with a few pieces of unused track, a spare arduino, DCC++ EX, JMRI and on a full PC at a desk?? Guess my limited knowledge of service mode... like what other than programming Loco decoders is service mode programming required?
There are some risks that make providing a safe, reliable programming spur on a small layout difficult. When programming a locomotive, the status responses involve pulsing the motor, so the locomotive will move some when it is being programmed or read back. Depending on the decoder, these pulses either alternate direction, or not. If not, the locomotive will walk along in one direction, and if that is back onto the normal layout track, then the locomotive can bridge the gap between the programming spur and the layout, thus causing every other locomotive on the layout to be mistakenly programmed. Some users reserve a section of track between the layout and the programming spur that is completely dead when the programming track is in use. This section needs to be longer than the longest locomotive. This can prevent a locomotive from shorting the programming track to the rest of the layout. But this makes your programming spur plus dead track even longer. On a small layout, this may not be practical. I would personally opt for a separate programming track away from the layout, especially if the layout was very small, unless I was willing to remove all other locomotives from the layout every time I was programming a locomotive (and in that case, I wouldn't need a separate programming spur on the layout either.) Preferably, the programming track should either be a small loop, or should have bumpers or some other means of preventing the locomotive from walking off the ends of the programming track.
Well you didn't mention that you had so much equipment. If you have all that I would just program on a short section of track off the layout. That is what I do. I have a couple pieces of foam three to four inches thick that I put at the end of the track. I would strongly encourage you to still get JMRI so you can use decoder pro. It is wonderful. You can download Steve Todd's image file onto a micro SD card in a couple minutes. Plug it into the pi and JMRI will come up on the screen. That is pretty darn simple. Sumner
Thanks for confirming what I've been researching that if another base station is available, no reason to have programming spur.
Sorry for the confusion. Guess most out rule totally separate system because of the cost for a commercially made secondary DCC system. But for about $25, cost of Arduino and motor shield, preference is to save the spur for general use in the layout. For sure, have used Decoder Pro connected via Windows laptop when programming a couple of loco's. Definitely the way to go. Will probably go with a Pi and Steve Todd's image for the layout since want function button labels pushed out to throttles or else think DCC++ EX wiThrottle Server would have been sufficient. Been using DCC++ EX with wifi as wiThrottle server for a couple of months now. Excellent. So actually, it seems that there are no pros to taking a layout spur that is part of the general layout, isolating rails for service mode programming if another DCC system is available for service mode programming. Also, outside programming loco's, curious what else have you used service mode for?? Thank you
... one can be running DCC. Isn't it wonderful that first Gregg and now Fred and everyone else now working on DCC++EX have made getting into DCC not much more expensive than buying a turnout, Sumner
Isn't it wonderful that first Gregg and now Fred and everyone else now working on DCC++EX have made getting into DCC not much more expensive than buying a turnout, Sumner[/QUOTE] Yes, what they have done is nothing less than outstanding. And, a tremendous contribution to the hobby enabling those with small layouts and budgets to experience DCC. The electronics-computer-controller stuff that they are doing is what attracted me back.
Heck, each decoder is as or more expensive than a DCC++ setup... And this is exactly the kind of stuff that will get/keep the young techies interested in model railroads!
Information for those that aren't into DCC now and wonder about costs. A number of my loco's have $16 decoders in them and I was getting $12 ones for a while. Hopefully that manufacture/supplier comes back as things settle down some. Not sound decoders, but doubt anyone would like a sound decoder in every loco they own if they have very many. So yes besides the DCC Command Station one still needs decoders but they don't have to all cost a ton, Sumner
Sumner, you are correct that cheaper decoders are (were?) available. But I have found that N scale locomotives seem to be sensitive to the quality of the motor drive control algorithms, and I like their programmable momentum with braking features. Those decoders (even without sound) are generally >$30 nowadays. Sound in N-scale locomotives disappoints me. I plan to use JMRI Virtual Sound Decoder instead. And yes, DCC & JMRI are what brought me back to model railroading too! I went the Pi SPROG 3 route. While more expensive than DCC++[EX], it is still a good deal.
Looked at Pi-SPROG, liked the product and will be my choice if unable to get Kato double crossover and/or turnouts to reliably work under DCC++ EX. Actually, curious on how people who are using DCC++ EX are controlling their turnouts, especially a Kato double crossover.
Note I have not tried it myself yet... still throwing mine manually. But I been thinkin' on it... The Kato Unitrack dbl x-over has all four switch machines wired in parallel, so it needs a lot of current to throw, unless you want to dig inside and separate the switch machine feeds. The Digitrax DS64 is the only stationary decoder I know of that will handle the dbl x-over, and on any one of the DS64's four outputs (so it could control up to four dbl x-overs independently). However, there are reports that DS64's, if controlled by DCC (rather than loconet), should be run/powered by a DCC signal that is not subject to shorts/interruptions during operation, or they may forget their settings. In other words, do not feed them from the same DCC signal that feeds the track. Either short-circuit protected power district(s) or booster(s) are needed, so the DS64(s) can be powered/controlled by the primary DCC output. You also cannot use the DS64's separate power input if you are using DCC to control it. That can cause the internal diodes to lose all their magic smoke, and give up the ghost.
Oh yeah, 36VA (per Kato packaging) for driving 4 solenoids simultaneously. I've done the same thing using MO DPDT but this is a "panel-less" design so want them to disappear by completion. Even considered using an ESP32 with built-in webserver and relays or another arduino + motor shield. Appears to be heading in that direction. Thought read somewhere that the switch-kat can throw d-xover but with its 1A max rating?? it would be interesting to test. I've sorta ruled out the DS64 yet it would suit the layout the best. In evaluating usage in a 1 DS64 layout, since is only one and knowing this "lose programming issue, assuming it reverts back to default settings a, might not nearly be an issue as bad as requiring a power down to reset DS64 say after a loco hits a point. To me, that's a deal breaker. Admittedly, haven't researched booster yet so for all I know, that could be the best answer. Any recommendations?
Keep in mind the DS64 uses a capacitive discharge system to energize the switch machine, so a 12V DCC bus does not have to deliver 3A when it switches the dbl xover. The DS64 charges a capacitor through a resistor, over a significantly longer time period than the discharge period, thus substantially reducing the DCC current needed to charge it. What booster or circuit breaker to use depends on the amperage needs of your layout (trackage) and how much capacity you already have. A single circuit breaker between the DS64 and the track (CS -> DS64(s) -> CB(s) -> Track) would do the trick, if the the CS has ample capacity, above the CB setting. Keep in mind any DCC stationary decoder used to control track switches will be unable to operate while the DCC bus controlling the decoder is shorted. And the problem with the DS64 may only be caused by trying to send it a command while the bus voltage is very low due to a track short (e.g. a command to try to clear the switch.)
Thank you for the info.. Yes, which enables Digitrax to spec the PS-314 power supply which is rated at max of 300ma for driving DS64 when connected via loconet. Assuming, the loconet connection only provides signal so the PS314 is doing the heavy lifting. Using the DIY motor shield on Mega, while its rated the same as the Arduino Motor Shield it has the larger HN package. While both are rated at 2 amps, Arduino real output about 1.2 so figuring about 1.5 amps. (a couple hundred milliamps higher due to package). Do you have a recommendation for breaker or booster? Presumably your notation [ (CS -> DS64(s) -> CB(s) -> Track) ] essentially means placing a single in line breaker in series with one track terminal of ds64 and the respective track? Thank you
Sorry for the late reply. DCC Specialties has circuit breakers that can be jumper-configured to trip at 1.27, 3.81, 6.35 or 8.89 Amps. The trip current can also be set via DCC to those levels, or other settings of 2.54, 5.08, or 7.62 Amps. Naturally, a circuit breaker has to trip at less than the main system ampacity, or the main system will trip first. The current the CB supplies is subtracted from the main CS ampacity. Boosters need a power supply (or a larger supply for both CS and booster), but they deplete the CS track bus capacity by only milliamps, leaving the CS fully capable of driving anything else. Tam Valley Depot makes a 3A continuous, 5A trip booster. SPROG makes a 2.5A booster (it can auto-reverse too). It includes a nice enclosure. There are likely others, but many are geared for higher currents.
Thank you very much for the info. Went to PiSprog site yesterday and downloaded sBoost datasheet. Thinking that the connection for DS64 should be as shown below?? Thoughts? Just looked at the TAM Valley booster and it looks like it can work as you suggest. Guess, besides price difference, the TAM Valley is smaller. (Only have about 1.4" underneath board) and haven't found SBoost dimensions but from the picture it does appear to fit.
