If I have a locomotive in which I installed a decoder to run in DCC, can it be run on a DC layout without removing the decoder?
Rich
Alton Junction
In most cases yes. AFAIK all modern decoders are dual mode, meaning that they can run on DC as well as DCC. Some of the older Soundtraxx decoders were not, and there may be others.
Also, realize that the DC function of the decoder can be disabled with a CV, so it is possible that it wont run if this has been done by someone. I always disable DC capability.
Do you know for sure the decoder that is in it?
Simon Modelling CB&Q and Wabash See my slowly evolving layout on my picturetrail site http://www.picturetrail.com/simontrains and our videos at http://www.youtube.com/user/MrCrispybake?feature=mhum
simon1966 In most cases yes. AFAIK all modern decoders are dual mode, meaning that they can run on DC as well as DCC. Some of the older Soundtraxx decoders were not, and there may be others. Also, realize that the DC function of the decoder can be disabled with a CV, so it is possible that it wont run if this has been done by someone. I always disable DC capability. Do you know for sure the decoder that is in it?
Sorry, I should have mentioned the type of decoder. It is a Digitrax D13SRJ. I have disabled the DC capability with a CV on the decoder.
richhotrain Sorry, I should have mentioned the type of decoder. It is a Digitrax D13SRJ. I have disabled the DC capability with a CV on the decoder. Rich
D13SRJ sounds like a NCE decoder to me, not Digitrax.
And you would have to re-enable the analog capability to get the loco to run on DC.
maxman richhotrain: Sorry, I should have mentioned the type of decoder. It is a Digitrax D13SRJ. I have disabled the DC capability with a CV on the decoder. Rich D13SRJ sounds like a NCE decoder to me, not Digitrax. And you would have to re-enable the analog capability to get the loco to run on DC.
richhotrain: Sorry, I should have mentioned the type of decoder. It is a Digitrax D13SRJ. I have disabled the DC capability with a CV on the decoder. Rich
Arghhhhhh, sorry again. Yes, it is an NCE D13SRJ.
So, instead of using the CV to disable DC, I would reverse the procedure and use the CV to enable DC?
Thanks.
richhotrain So, instead of using the CV to disable DC, I would reverse the procedure and use the CV to enable DC? Thanks. Rich
Yes
maxman richhotrain: So, instead of using the CV to disable DC, I would reverse the procedure and use the CV to enable DC? Thanks. Rich Yes
richhotrain: So, instead of using the CV to disable DC, I would reverse the procedure and use the CV to enable DC? Thanks. Rich
Excellent. Thanks for that input.
What am I missing here? I thought there were dire consequences for decoders if they ran in DC. Just when I thought I was understanding things, this one throws me for a loop.
Doug, there most certainly were, Soundtraxx LC decoders for instance, and may still be, decoders that could not be run on DC. Every decoder I have installed in the past few years from NCE, Digitrax, TCS, Lenz, QSI and Soundtraxx Tsunami have been dual mode, meaning that the DCC decoder can be safely operated on DC.
Doug from Michigan What am I missing here? I thought there were dire consequences for decoders if they ran in DC. Just when I thought I was understanding things, this one throws me for a loop.
Doug, as the OP of this thread, I would have thought the same thing at one time.
My first hint that a DCC equipped loco could be run on DC is the fact that in programming the decoder, the question is asked whether to set the decoder for DC operation.
I am thinking of selling some of my DCC equipped locos on eBay, and it crossed my mind that DC users might be interested in purchasing one or more of these locos. So, I began to wonder if the decoder could be reset to DC so that i wouldn't have to remove the decoders before sale. In my mind, a DC guy who purchases such a loco has the advantage of being able to reset the decoder once again to DCC if he decides to go in that direction later on. Of course, the disadvantage of the decoder to the DC user is that he is paying for something that he doesn't need. My problem is that I am stuck with an used decoder if I sell the loco without it.
Rich, sell with the decoder, I would rest all address back to 3. Just mention the engine can be ran on DC as well as DCC. You will have more buyers that way.
By the way, what are you selling?
Ken
I hate Rust
cudaken Rich, sell with the decoder, I would rest all address back to 3. Just mention the engine can be ran on DC as well as DCC. You will have more buyers that way. Ken
I thought that it would be better to set the decoder back to running on DC so that a DC buyer could just run the loco right out of the box. Otherwise, how could a DC user change the CV setting?
richhotrain Doug from Michigan: What am I missing here? I thought there were dire consequences for decoders if they ran in DC. Just when I thought I was understanding things, this one throws me for a loop. Doug, as the OP of this thread, I would have thought the same thing at one time. My first hint that a DCC equipped loco could be run on DC is the fact that in programming the decoder, the question is asked whether to set the decoder for DC operation. I am thinking of selling some of my DCC equipped locos on eBay, and it crossed my mind that DC users might be interested in purchasing one or more of these locos. So, I began to wonder if the decoder could be reset to DC so that i wouldn't have to remove the decoders before sale. In my mind, a DC guy who purchases such a loco has the advantage of being able to reset the decoder once again to DCC if he decides to go in that direction later on. Of course, the disadvantage of the decoder to the DC user is that he is paying for something that he doesn't need. My problem is that I am stuck with an used decoder if I sell the loco without it. Rich
Doug from Michigan: What am I missing here? I thought there were dire consequences for decoders if they ran in DC. Just when I thought I was understanding things, this one throws me for a loop.
Wow. Well thanks for your original post Rich!
We only have two locos with decoders, both of them being DH163's. The only programming I did on each was to set the address, and I don't recall being prompted on the DC/DCC thing. I guess I need to spend some time on the Digitrax site to learn a little more about my decoders.
This is a blessing for us, as we're wired up to run both DC and DCC (with the appropriate precautions taken to prevent mixing of the two) so my son can still run his Bachman Thomas engines. While he's doing that, the DCC locos are either parked on yard tracks with toggles to turn track power off, or they're just taken off the layout. We've been running succesfuly like this all summer. But I still expected that the safety protocol wouldn't be followed at some point, and I'd be off to the LHS for more decoders.
Doug, one of the regulars that attends the K-10 model trains running sessions, where kids get to run on the 4K sq ft layout has a Bachmann Thomas converted to DCC with a sound decoder. It works great, but has to be the most annoying thing to be around, constantly whistling away!!
Doug from Michigan Wow. Well thanks for your original post Rich! We only have two locos with decoders, both of them being DH163's. The only programming I did on each was to set the address, and I don't recall being prompted on the DC/DCC thing. I guess I need to spend some time on the Digitrax site to learn a little more about my decoders. This is a blessing for us, as we're wired up to run both DC and DCC (with the appropriate precautions taken to prevent mixing of the two) so my son can still run his Bachman Thomas engines. While he's doing that, the DCC locos are either parked on yard tracks with toggles to turn track power off, or they're just taken off the layout. We've been running succesfuly like this all summer. But I still expected that the safety protocol wouldn't be followed at some point, and I'd be off to the LHS for more decoders.
Which prompts the question, what happens if you try to run a DCC equipped loco on a DC layout with DCC enabled on the decoder? I sure don't know the answer.
Give me $20 and I'll find out
Doug from Michigan Give me $20 and I'll find out
OK, Doug, here is the deal.
You run a DCC equipped loco, your most valuable one, on a DC powered layout without any adjustments to the decoder. Then, come back and tell us what happened. We can then decide the best way to reward you for your efforts.
If you set CV29 to turn off the automatic analog conversion (DC) mode, nothing happens. It just sits there, provided the DC voltage does not exceed the maximum input voltage of the decoder.
We have two loco cleaning options on the club layout. One is a Bachmann DC power pack hooked to one of those Kadee wheel cleaning brushes, the other is a section of track hooked to a DB150 with a throttle plugged in. I never use the Kadee brush because I always turn off DC in my decoders, I use the DB150 track and a paper towel soaked in alcohol to clean my loco wheels.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I ran a Kato SD40-2 DCC on DC and it started smoking so i stoped it but it still runs.
Russell
CV 29 is used to enable/disable DC running, however CV13 and 14 are used to turn on function keys on many decoders. CV29 will just enable the motor. 13 and 14 will enable the lights and sound.
I have found MRC 324 decoders flaky on DC running, but in large scale all Zimo and LGB decoders work on DCC and DC as well as MTS.
All this make's me want to know. What is the advantage or maybe what is the pupose of disableing analog mode?
Is there any problem running them with analog mode inabled?
Larry
mrgstrain All this make's me want to know. What is the advantage or maybe what is the pupose of disableing analog mode? Is there any problem running them with analog mode inabled? Larry
I'm not sure of the exact technical explanation, but as I understand it there is a DC component to the DCC signal (or something that looks like DC to the decoder). And when the track (or the loco) is first fired up, that DC component gets to the loco first. And when this happens the decoder thinks it is seeing DC and the unit will run away out of control. I don't know if this is a problem with the current breed of decoders, but it used to be a problem with earlier decoders. Anyway, to prevent this from happening, the advice was to disable the analog mode.
I'm sure someone can chime in with a more correct technical explanation if I have any of the details wrong.
If the track power comes up before a stable signal is generated from the command station, a decoder set to allow analog conversion MIGHT see that as DC, and all that really does in the decoder is turn on the motor drivers, so the track power goes right to the motor, minus a little bit for the drop inside the driver electronics. In such a situation, the loco can suddenly take off in one direction or another.
The below link might shed some light.
http://www.wiringfordcc.com/runaway.htm
Be advised, a motor never sees direct track voltage from a decoder. The motor sees what the micro processor sends to it via the motor drivers. Either positive or negative going pulses, PWM. The track voltage goes right to the micro processor first. If the processor gets confused, it might not pick out the correct program from the ROM on the decoder.
The track voltage also goes to the bridge rectifier to develop the DC voltage operate the decoder.
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
What is the advantage of disabling DC in a dual mode decorder?
Joe Staten Island West
joe323 What is the advantage of disabling DC in a dual mode decorder?
Read though some of the responses. It has been mentioned.
If you sell your DCC loco to a DC guy, he will NOT be able to change it back himself, because he has no DCC gear that will do this for him. Well, ok, *I* can do it: I open up the loco, remove the offending electronics and wire it my way.
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
If it's a plug-in decoder or you otherwise didn;t cut wires or modify it, you can sell the decoder too. Probably get more by sellign them seperately as well. On the other hand, plenty of people would like a loco they can just take out of the box and put on the track, without having to install a decoder.