Rick, I don't even use DCC: I use DC. Even so, I ended up with a problem identical to yours years ago and after weeks of trying to solve it, felt like just giving up. Turned out it was the Controlmaster 20's walk-around, plug-in throttle that was doing it. I bought a new throttle and problem solved. My point is that I had none of the DCC components but still had the problem. It wasn't my problem and had nothing to do with shorts or anything. It was just a throttle.
Chaya, Funny, but I remember we talked about that. Odd how things can happen. By the way good to hear from you I was thinking about you the other day wondering if you might drop in on this discussion. I figured your engineering degree might come in handy here. For now I think we have things back up and running. We will be swarming the layout again but this time as a work bee. We will put in additional wire drops, a block or two and dig into the control panel to see where a short is coming from. For now the owner of the layout is a happy camper. YoHo, We don't have a club with a pecking order and someone in charge. We are a round robin group and the idea here is for everyone to learn to master DCC. You have to know how to run your own layout...or...what's the purpose. No master model railroaders assigned to specific tasks. Don't get me wrong we have qualified NMRA master model railroaders in the group and yes we rely on them heavily. But they don't wear it on their sleeve and lord it over the rest of us. We kind of like that. YoHo, thanks for your input. I took from it what I needed as well as compared it to thoughts shared by other electronic engineers, electricians and other engineering credentialed degree types. You fine folk are an asset to this hobby. Good to have you on board. I cleaned up BarstowRick.com. Re: DCC friendly switches. Feel free to comment, redirect and or add to the discussion. That includes all of you who participate here. Can we kill a decoder and the quick answer is yes. It will be a rare day when we kill another one. Thanks all for tuning in here.
Chaya, Almost forgot. My layout has DCC hard wired in via a DPDT. However, the only two DCC diesels I had have been forced back into the ranks of Analog DC. I won't be running DCC on my layout until I can afford the decoders or I get my head wrapped around it. So, I'm no expert on the subject but lean heavily on those who are. That's a wrap.
I wasn't trying to suggest that you needed to have the formal structure of a real club. I was suggesting that novice DCC people SHOULD NOT PROGRAM ON THE MAIN until they have more experience. And I illustrated that my club had instituted rules to that effect. Of course you can do what you want, but I won't feel bad about fried decoders and misconfigurations for those that don't take the baby steps that are recommended. Programming on the main is dangerous. use the programming track, that's what it's there for.
My point exactly. Again no argument there until we start talking about feelings and the fact these are individual layouts. We respect that each layout is governed by it's owner. As a result they set the standards, make the rules and you know the rest. Each member of the group is taking the baby steps even if they do it backwards. Sigh! Today, what I learned from my fellow BVMR's. while sitting at CJ's, is the CV's #'s 6, 8 & 9 will set a decoder back to factory default. What number goes to what decoder, is the nagging question. Then keeping track of what locomotive or diesel and the decoders inside them. Well, that's another question.:startled: Still tickling these keys on my lap top as I know there is a CV you can go to and you must enter a number to zero it out and this sets the locomotive or diesel back to factory default. Each decoder is different and usually you can find this default setting in the instruction sheets that come with it. As a group we are learning more about DCC and how it works. You will find one Digitrax, one NCE and three MRC command stations powering up as many layouts. The differences in how each works.... that can be confusing. We find ourselves learning more then one system. Now that can't be all bad. Certainly not easy. One more time a shout out of thanks.
Rick, If you check the NMRA standards, I believe you will find that setting CV8 to 8 is supposed to reset a decoder back to the factor defaults. Also, may be one of your members might want to install JMRI and play with DecoderPro3.
The factory reset procedure differs between brands of decoders. They are not all the same. Setting CV8 = 8 works for many but not all decoders. Here is a list from the NMRA web site. Lenz CV8 = 33 NCE CV30 = 2 Digitrax CV8 = 8 LokSound (ESU) CV8 = 8 Train Control System CV8 = 8 or CV30 = 2 SoundTraxx: DSDLC, DSX Tsunami CV30 = 2 CV8= 8 MRC (New) CV125 = 1 Note: I don't know if the NMRA list above is up to date. - Jeff
Jeff: That short list is up to date. For a more comprehensive list of decoders go to the NMRA site. http://www.nmra.org/index-nmra-standards-and-recommended-practices See appendix 9.22 Shades
Shades - Thanks for the link. S-9.2.2, Appendix A is list of NMRA-assigned DCC manufacturer ID codes: http://www.nmra.org/sites/default/files/standards/sandrp/pdf/appendix_a_s-9.2.2.pdf It's nice to have that list. However, I don't see an updated list of decoder factory reset codes. Did you find such a list? - Jeff
jeff: That list was revised March 6, 2015. That's about as good as it gets. What most modelers need to know is that CV8 isn 't an automatic re-set to factory defaults for all decoders. You must get a read out of what decoder is in each locomotive that you want to re-set the values in to factory defaults. Thanks for listing the CV values you originally listed. I used those values in an article on my blog rather than the much expanded list I just posted. Shades
Jeff and Shades. With regards to CV's and reset values. Wow, I go away thinking we are at the end of the tether (rope) and Jeff comes to the rescue. Then Shades jumps in with affirmation and usable news highly valued by this hobbyist. A shout out of thanks to the both of you. I saved the PDF from NMRA to look at later today. I couldn't wait and took a sneek peek. Has anyone really looked at that. Gosh, I can't make heads or tales of the information provided. http://www.nmra.org/sites/default/fi..._a_s-9.2.2.pdf One more question I can read CV8= Uhh...err...what does the equal stand for and the number that follows. Is that the number you enter into the CV to zero it out?
Appendix 9.22 is really easy Rick. All you have to remember is the memufacturer and the re-set id number. For example Digitrax' ID number is 129. The re-set number is CV 8 = 8 Lenz' ID number is 99. The re-set number is CV 8 = 33 Hope this helps. Shades
Thanks again, and that comes from Stubby E., Steve H., and others here in the Bear Valley region of the San Bernardino mountains.
Rick, for the most part you can't go wrong with knowledge shared by TB members. That's what is great about this hobby, guys and gals helping each other. Carl
I've never been steered in the wrong direction and it would never be my intent to do so when it comes to the fine folk here on TB and those who visit BarstowRick.com. I share my two cents worth but hey, that can be ignored. I will be posting the help I got here on BRick.c Thanks for your help Carl and that goes for the others.
Whow. You came close to the problem but missed it on several levels. With out looking underneath the layout I can see twisted pair wiring and high voltage spikes. I have tried to send MRMag my article but they refused to publish it. Snubbers are BS. Yes an occurrence of shorts do occur and they are deep inside the decoder. Yes unexplained heat builds up happens when induction shifts the power factor. No one can see the actual voltage spike even when using an oscilloscope. Yes, more running loco causes sooner failure. The DCC power is a square wave and does not have a frequency. The switch time causes the spikes. I removed all twisted pair wiring on a 100 by 40 foot layout and it solved similar problems. MRC has an extra step in the DCC switch time because it can be seen on the oscilloscope and it helps to lower spikes. Those spike happen when the twisted wire builds a magnetic field and the current is changed fast as with the edge of the DCC signal. Induced voltage will happen at the speed of light so the oscilloscope gives a bad representation. Check the wiring. Dave
Dave, First, congratulations on your first post on TrainBoard. In case you didn't notice, this is a six year old thread that you have ripped open...
I know how old the thread is and then a proper reply is always a welcome sight no matter how late it comes. I have tried for years to show a definitive response to what happens in twisted wires with a seven page article I wrote. It was intended to go to several magazines but the publisher thought it wasn't necessary. It clearly shows the misconception of what twisted pair wires do to the decoders. I have included electron microscope images to prove this and explained that outside noise can not impose noise on the leading edge of a DCC signal because the so called noise has no idea of when a one or zero is sent therefore it comes from itself. I'm now retired and have more time to post the information and congrats. I started here. Dave
