alangr Posted March 30, 2015 Share Posted March 30, 2015 I am using a DCC Concepts Zen decoder ‘with stay-alive’ to help enhance the running of some locos (e.g. 4-wheel Pug, motorised tram). As I still had poor running after installation, I decided to investigate further. I set up a separate piece of track with a DCC feed. The loco ran OK but stopped dead when the feed was removed. I then attached a separate 4700uF capacitor to the decoder and tried again – with the original capacitor in parallel and also the new one by itself. With each trial the loco appeared to stop dead. And, yes, I did have the polarity of the (electrolytic) capacitor correct! All this perplexes me as although I was not expecting a large over-run when the power was removed, I was hoping for at least some slight pause before the loco stopped. Any ideas? Link to post Share on other sites More sharing options...
Adrian Wintle Posted March 30, 2015 Share Posted March 30, 2015 I am using a DCC Concepts Zen decoder ‘with stay-alive’ to help enhance the running of some locos (e.g. 4-wheel Pug, motorised tram). As I still had poor running after installation, I decided to investigate further. I set up a separate piece of track with a DCC feed. The loco ran OK but stopped dead when the feed was removed. I then attached a separate 4700uF capacitor to the decoder and tried again – with the original capacitor in parallel and also the new one by itself. With each trial the loco appeared to stop dead. And, yes, I did have the polarity of the (electrolytic) capacitor correct! All this perplexes me as although I was not expecting a large over-run when the power was removed, I was hoping for at least some slight pause before the loco stopped. Any ideas? You might want to read their description of thier Stay-Alive. They only claim fractions of a second. It is more to keep the decoder alive over momentary power interuptions/fluctuations. At the bottom of this document: http://www.dccconcepts.com/vamr/dcc-advice-12-exerpt-b-decoder-standard-connectors-and-stay-alives Adrian Link to post Share on other sites More sharing options...
alangr Posted March 30, 2015 Author Share Posted March 30, 2015 You might want to read their description of thier Stay-Alive. They only claim fractions of a second. It is more to keep the decoder alive over momentary power interuptions/fluctuations. At the bottom of this document: http://www.dccconcepts.com/vamr/dcc-advice-12-exerpt-b-decoder-standard-connectors-and-stay-alives Adrian I was aware of this which is why I tried out the 4700mF condenser. Much too big to fit in the model but at least I could see the effect on performance. This said, the range of stay-alive capacitors offered by youchoos suggest that using a 6800uF could give around 1.5 seconds - see link below. OK, it may not be a proportionately linear relationship, but I would still be able to see some effect on the 'run-on' using something around 2/3 of the value of the capacitor that they mention. Unless, of course, there is more to it that I am aware of and there are some fancy things going on behind the scenes! With what happened, I am somewhat unsure of how to go forwards! Thanks for your comments. Alan http://www.youchoos.co.uk/Index-Shop.asp?L1=Electronics Link to post Share on other sites More sharing options...
OOgaugeJaf Posted March 30, 2015 Share Posted March 30, 2015 Some of the YouTube videos showcasing these stay alive chips show the locomotive running a good distance without power. Possibly look at these and compare products. I want something for a Hornby Sentinel, any suggestions? Link to post Share on other sites More sharing options...
Nigelcliffe Posted March 30, 2015 Share Posted March 30, 2015 In my experience of stay-alive, the numbers being talked of (few thousand uF) will only give fractions of a second of running time. It is enough to make a difference to running (so I'll fit a capacitor to small locos when I can), but it doesn't do party tricks of running without track power. What you actually see as run time depends on numerous factors; the circuits in the decoder, the power draw of the motor, the actual track voltage, and so on. If you really want seconds of run time, increase the capacitance. A capacitor bank of around 0.15F will delivery about 30 seconds run time in a 4mm scale loco. Such things need not be huge if you use super-caps. Link to post Share on other sites More sharing options...
alangr Posted March 30, 2015 Author Share Posted March 30, 2015 I agree that the picture is just not straightforward but I am not looking for anything exotic. The Zimo SC68 (6800uF) is quoted as giving around 1.5 seconds running without power ( see youchoos website and RM February 2015 page 113). Even if these figures are exaggerated by a factor of two, some slowing down before stop should be seen with a 47oouF, I reckon. So I am still wondering what I am doing wrong! Alan Link to post Share on other sites More sharing options...
Adrian Wintle Posted March 30, 2015 Share Posted March 30, 2015 What is your decoder set to do on DC? Adrian Link to post Share on other sites More sharing options...
34theletterbetweenB&D Posted March 30, 2015 Share Posted March 30, 2015 ...I set up a separate piece of track with a DCC feed. The loco ran OK but stopped dead when the feed was removed. I then attached a separate 4700uF capacitor to the decoder and tried again – with the original capacitor in parallel and also the new one by itself. With each trial the loco appeared to stop dead. And, yes, I did have the polarity of the (electrolytic) capacitor correct! All this perplexes me as although I was not expecting a large over-run when the power was removed, I was hoping for at least some slight pause before the loco stopped. Any ideas? The stay alive description I have read is designed to work as described. Motor supply from the decoder ceases the moment the DCC signal is no longer detected. Repeat your experiment with a piece of insulating tape over one rail of somewhat greater length than the pick up span of the loco, and see if it runs over that. Link to post Share on other sites More sharing options...
RMweb Gold john dew Posted March 30, 2015 RMweb Gold Share Posted March 30, 2015 Hi Alan Its been a long time.......hope you are well. I havent used DCC Concepts Zen decoders/stay alive but I did try out their original stay alive product and I am afraid they were not very satisfactory. The Lenz product works well but is very expensive as you have (or had to?) link it with a Lenz Gold Decoder. I normally find Lenz standard fine for my needs! Where I have to have power back up (Hornby 14xx for example) I find TCS decoders with KAT (keep alive ) are excellent......this poor video is a good demonstration https://www.youtube.com/watch?v=ml_a3RgDCT8 Regards from an overcast Vancouver Edited.....I should add that in the video I refer to "stay alive" in the generic sense........the autotrain is fitted with "Keep Alive". The problem that I omitted to mention is that KAT capacitors are quite large....I think you might struggle to get one in a Pug Link to post Share on other sites More sharing options...
deadlyduck Posted March 30, 2015 Share Posted March 30, 2015 Size for size the Best Stay alives are the TCS KA1/2.The DCC concepts 1s are not that clever,would you be able to fit a TCS-DP2X-UK into the pug ? Link to post Share on other sites More sharing options...
Ron Ron Ron Posted March 30, 2015 Share Posted March 30, 2015 The different decoder manufacturers offering Stay Alive or Keep Alive, have approached the issue from slightly different angles, with different objectives and as a result Stay Alive or Keep Alive, comes in different forms. They are not all the same. As an end user, I think one has to decide what they want this feature to do and choose an appropriate brand and their products accordingly. IIRC, DCC Concepts solution is only designed to overcome split second interruptions in the power supply and to smooth out the power supply, whether receiving good track power, or through those momentary interruptions. Their Stay Alive will not allow a loco to run on and on. On the other hand, TCS designed their Keep Alive solution to run on over breaks in the power supply, such as dead frogs, so if power is cut (without a command) the loco will carry on. Here is a TCS video, showing a Keep Alive fitted loco carrying on over approx. 18" of dead track. The expensive Lenz USP set-up, using their Power 1 and 3 modules, goes one better, allowing DCC commands to be received and acted upon, whilst the loco is not receiving power from the live tracks. Link to post Share on other sites More sharing options...
peter220950 Posted March 30, 2015 Share Posted March 30, 2015 Not forgetting Zimo, which has managed 4 sheets of A4 in my Fowler, though the size of 6 supercaps is probably an issue for 00. Though I should say it's programmable to shut down if it doesn't receive a command within a set time, and at present is used as a party piece rather than a sensible period of >.5second to use the function more correctly. Link to post Share on other sites More sharing options...
chaz Posted March 30, 2015 Share Posted March 30, 2015 Just a thought - are you allowing your model enough time to charge up the capacitor(s)? When I first tested my O gauge 0-4-0ST with an ESU PowerPack fitted to the Loksound decoder (their name for a KA or SA) it didn't seem to help at all, stalling as frequently as it had before installation. However after a minute or two it was transformed. Most KA circuits include a resistor in the charging circuit which prevents a large charging current from triggering a DCC shutdown at switch-on. This will make the charge build up slowly and you may need to wait a short time to get the full effect. Hope that helps? Chaz Link to post Share on other sites More sharing options...
alangr Posted March 31, 2015 Author Share Posted March 31, 2015 Thank you all for your comments; they leave me with much to think about! The exposition on the two, essentially different, approaches to keeping/staying alive is clearly more than somewhat important in all this and I certainly had not appreciated the nature of the differences. That said, I can certainly see that DCC Concepts would adopt the approach that it has – micro control of brief hiccups and smoothing generally while taking a baseline of a good model, good connections and good pickups. Just as it should be, I guess. However, the approach taken by the TCS ‘keep alive’ is more what I am after as the models I need to ‘fix’ are not the usual locos. One is a motorised tram with two double-axle bogies (wired in parallel) where the pickup is not brilliant and even a 0.2 second delay would be helpful (and 0.5 seconds really good). The other is a Pug which with four wheels is not very good at running slowly. To adopt the TCS keep alive probably means going for a TCS decoder in order to avoid mixing manufacturers and thus getting into possible compatibility problems (or damaging something!). It is also interesting to see that TCS offer a package that has a decoder plus keep alive all in one – for a price, of course! The question of space is an issue but nothing comes for nothing so a shoehorn will be needed. In other cases (e.g. the Pug) it may simply not be possible to do what I want without really major surgery. I have a Lenz setup but had overlooked the Gold decoder/USP modules as I did not want to make the whole thing too expensive; maybe I should re-look at this as the approach taken is the way I want to go. There was likely to have been no problem with the charging of the condenser as (perhaps stupidly) did not include a charging resistor (or diode) in my trial When I ‘disconnected the feed’ to the test track it was only one side so much the same as the insulating tape suggestion, I guess and as for the DC setting (CV29 bit2) it was zero. Thanks again all. Alan Link to post Share on other sites More sharing options...
Ron Ron Ron Posted March 31, 2015 Share Posted March 31, 2015 Here's another demo of the TCS Keep Alive device, this time added to a Tsunami sound Decoder in place of the Tsunami keep alive. Watch for the end of the demo, when the presenter lifts the loco off the tracks. Link to post Share on other sites More sharing options...
deadlyduck Posted March 31, 2015 Share Posted March 31, 2015 Thank you all for your comments; they leave me with much to think about! The exposition on the two, essentially different, approaches to keeping/staying alive is clearly more than somewhat important in all this and I certainly had not appreciated the nature of the differences. That said, I can certainly see that DCC Concepts would adopt the approach that it has – micro control of brief hiccups and smoothing generally while taking a baseline of a good model, good connections and good pickups. Just as it should be, I guess. However, the approach taken by the TCS ‘keep alive’ is more what I am after as the models I need to ‘fix’ are not the usual locos. One is a motorised tram with two double-axle bogies (wired in parallel) where the pickup is not brilliant and even a 0.2 second delay would be helpful (and 0.5 seconds really good). The other is a Pug which with four wheels is not very good at running slowly. To adopt the TCS keep alive probably means going for a TCS decoder in order to avoid mixing manufacturers and thus getting into possible compatibility problems (or damaging something!). It is also interesting to see that TCS offer a package that has a decoder plus keep alive all in one – for a price, of course! The question of space is an issue but nothing comes for nothing so a shoehorn will be needed. In other cases (e.g. the Pug) it may simply not be possible to do what I want without really major surgery. I have a Lenz setup but had overlooked the Gold decoder/USP modules as I did not want to make the whole thing too expensive; maybe I should re-look at this as the approach taken is the way I want to go. There was likely to have been no problem with the charging of the condenser as (perhaps stupidly) did not include a charging resistor (or diode) in my trial When I ‘disconnected the feed’ to the test track it was only one side so much the same as the insulating tape suggestion, I guess and as for the DC setting (CV29 bit2) it was zero. Thanks again all. Alan 1 option i would suggest isd 1 TCS DP2X-UK-KAC this comes with a 2 pin plug if you can fir this in your pug therea a TCS Stay alive with a 2 pin plug which attaches into the other 1 KA-1C you could put this into a wagon with a cover on it.As the TCSs have the plugs it doesnt need to be permanant Link to post Share on other sites More sharing options...
alangr Posted March 31, 2015 Author Share Posted March 31, 2015 The demos are very impressive - 'I think I want what their having'! Yes, the idea of splitting the decoder and the keep alive is as tempting as getting them as a single unit - clearly for different reasons! Thanks both Link to post Share on other sites More sharing options...
deadlyduck Posted March 31, 2015 Share Posted March 31, 2015 The demos are very impressive - 'I think I want what their having'! Yes, the idea of splitting the decoder and the keep alive is as tempting as getting them as a single unit - clearly for different reasons! Thanks both No problem im doing it with my BR steam.I have on a couple of occasions where space is very limited used a DCC Concepts decoders (3) with a TSC keep alives nothing untowards has happened Link to post Share on other sites More sharing options...
chaz Posted March 31, 2015 Share Posted March 31, 2015 . There was likely to have been no problem with the charging of the condenser as (perhaps stupidly) did not include a charging resistor (or diode) in my trial When I ‘disconnected the feed’ to the test track it was only one side so much the same as the insulating tape suggestion, If you were wiring the capacitor to solder pads provided for it on the decoder it's possible that the decoder itself include a current limiting resistor. Chaz Link to post Share on other sites More sharing options...
deadlyduck Posted March 31, 2015 Share Posted March 31, 2015 A have also started to build my own keep alives,withe Zimo decoders some you just wire the capacitors onto the decoder,while other Zimo decoders you can use TCSs.If you can get the Zimo catalogue not the download 1.All the info into what decoder does what is in it Link to post Share on other sites More sharing options...
shibushe Posted March 31, 2015 Share Posted March 31, 2015 I to have had problems with DCC Concepts Stay alives even those without this feature. some of there other products are not to clever either. I prefer now to go elsewhere. The best stay alives I have used are those from TCS. Infact most of my decoders are from this company, great back up to. Ether phone or email. Link to post Share on other sites More sharing options...
pauliebanger Posted March 31, 2015 Share Posted March 31, 2015 I to have had problems with DCC Concepts Stay alives even those without this feature. some of there other products are not to clever either. I prefer now to go elsewhere. The best stay alives I have used are those from TCS. Infact most of my decoders are from this company, great back up to. Ether phone or email. Shibushe, This is an enquiry not a challenge. You have some experience of TCS KA packs. Do they operate the same on DC? i.e., if you run the loco on analogue, and lift it from the track with the motor running, does it continue to run? Kind regards, Paul Link to post Share on other sites More sharing options...
RMweb Gold SHMD Posted March 31, 2015 RMweb Gold Share Posted March 31, 2015 Would it be fair to rename these features "Keep Thinking" and "Keep Moving" instead of their trade names above? (Although both still lose coms.) Kev. Link to post Share on other sites More sharing options...
pauliebanger Posted March 31, 2015 Share Posted March 31, 2015 Here's another demo of the TCS Keep Alive device, this time added to Tsunami sound Decoder in place of the Tsunami keep alive. Watch for the end of the demo, when the presenter lifts the loco off the tracks. Similar result for less money using guidance published in Hornby Magazine issue 88: Stay alive effect from circa 2 minutes 30 secs https://youtu.be/l7W_Q6b-lwc Kind regards, Paul Link to post Share on other sites More sharing options...
alangr Posted April 1, 2015 Author Share Posted April 1, 2015 I am going to try out the KAT12 from TCS. It is not small but should fit into my motorised tram OK. While I am doing that I can see if there is any possibility about doing the same in a pug - I doubt it but, hey, it's worth a go! Good to have the comments generated here: thanks to all. The noting of the differences in approach (i.e.keeping or staying alive) were especially helpful. Thanks, John, for the good wishes - I have sent you a PM rather than reply here. Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.