Burning subject about incandescent lights on DT v. NCE systems

[OldEastRR]

Hey hi you might remember me as the guy with the melting RDCs and DCC frustration? Turns out the Digitrax track voltage was also supercharging the lightbulbs in my first-run KATO car lighting kits and in turn melting the plastic of the roofs above them. Luckily all but one of my KATO cars has a double ceiling (car body then outside roof) so only the inner walls got fried, some literally black. So you might remember my thread about what to do about that, since I liked the warm glow of lightbulbs over LEDs. That one went down the path of installing resistors in the bulb circuit to cut down voltage, but watch out you use too small a resistor and it gets as hot as the damn bulb.
OK, in the midst of this fleet rebuilding job I finally want to get rid of the borrowed DT Zephyr I was using and bought an NCE PowerCab. Difference like night and day in performance and satisfying operation.
However, I noticed the resistor-equipped light bulbs looked noticeably dimmer with the NCE system. So I tried a unmodified light bulb car, with the shell in place, and left it on. Besides not as bright as with the DT power, they also didn't overheat and melt any plastic. Didn't even discolor their plastic hoods.so WTF?

Is Digitrax track power way more than NCE track power?

 The club I used to run my stuff on also had Digitrax and the lightbulbs burned plastic on that system too, which obviously wasn't a Zephyr.
Needless to say, I won't be adding resistors to my lighting circuits anymore, and now have to tear out the mods I did. So thanks DT, for melting my cars and putting me through extra needless work on them. For that kind of ****, you're the best.
P.S. I am curious to see how the RDC LEDs react to this new system, but I'll have to wait for the replacement boards for the ones I burned up and/or butchered to try to stop the overheating. Thanks, again, Digitrax!!!
Wow, auto-censoring on TRW .... what will they think of next? 

[peteski]

P.S. I am curious to see how the RDC LEDs react to this new system, but I'll have to wait for the replacement boards for the ones I burned up and/or butchered to try to stop the overheating. Thanks, again, Digitrax!!!
Wow, auto-censoring on TRW .... what will they think of next? 

I thought that we beat the RDC light board subject  to death already (and that a solution was provided).
The brightness level of LEDs  (with series-resistors of course) doesn't change as dramatically as incandescent bulbs when the DCC voltage varies by few volts.

[cgw]

I sense your frustration with the equipment but you need to do some checking first before blaming the equipment for your woes......     what was the scale setting in and what is your power supply setting.    the scale setting limits the upper voltage that the command station/booster puts out to the track.       It needs to be set in the N setting.  This limits the voltage to about 12 volts.   the H/O setting is set at 15 volts and O/G setting at 20 volts.     The voltage output can be fine tuned further by adjusting the trimmer pot inside the unit.        Flipping this switch to the wrong scale is the number one reason for the melt down of incandescent bulbs.   If the track voltage applied exceeds the operating parameters of the locomotive and it’s LEDs/lamps, damage to the locomotive or decoder may occur.  Most HO & N Scale locomotive motors, LEDs, and lamps are designed to operate on 12 volts DC on the track. Z Scale equipment is designed to run at 9 volts.  Digitrax recommends running your command station and boosters at the lowest track voltage possible that provides acceptable operation.   For the z scale stuff you can get the voltage reducer diode array from MRC or Digitrax that will nock the voltage down to 9 volts. When you pick your current limit resistor value make sure you size it the highest possible input voltage that you locomotive will see on the track  The power supply need to be sized for the current and voltage for the command station/booster unit.    For a n scale setup  a 15volt 5 amp power supply is adequate.

[OldEastRR]

I'm not frustrated or complaining about the NCE system at all -- I love it!

Let me state my query more distinctly: Is there a difference in the voltage between Digitrax and ESU track power?

All the other stuff in my OP was not germane.

[cgw]

yep big time difference    nce, digitrax for n scale 12v    the esu cranks out between 15/16 volts. at the lowest setting    . As stated before size your current limiting resistors  to the maximum voltage  you are going to apply.

[peteski]

yep big time difference    nce, digitrax for n scale 12v    the esu cranks out between 15/16 volts. at the lowest setting    . As stated before size your current limiting resistors  to the maximum voltage  you are going to apply.

ESU?!  How did we get to ESU (that question is for Al).  And yes, there there are difference in the track voltage between various brands DCC boosters. Some depend on external power supply which introduces another variable to the voltage equation.

[OldEastRR]

Sorry -- I mean like the thread title says, difference in voltage between NCE and DT. I have mostly LokSound decoders. But obviously the voltage going into the DT system is higher than that going into NCE, the fact my lites are not as bright as on the DT power is a pretty clear indication of that. There's no confusion there:
DT - lite bulbs get so hot they melt plastic car bodies
NCE- lite bulbs get extremely warm but not enough to melt or deform car bodies.
OBVIOUSLY the voltages are different, but why?

I believe here the answer is, DT is just a shitty system, period.

[peteski]

While I strongly dislike Digitrax DCC in general, I would not call it crappy strictly going by the booster's output voltage to the track.

It is what it is. I don't think that the official NMRA DCC specifications define what the track voltage should be. So, different manufacturers use what thy think is appropriate voltage.  As it has been mentioned, it appears that Digitrax output voltage is adjustable (so you can crank it up for larger scale models).

NCE PowerCab is a basic DCC system with a small 13.8V wall-wart power supply. The booster drops couple of volts on the output transistors, so you end up with around 12V a the track.  Good or bad - that's what it is.

[cgw]

Dude you need to take a chill pill.    I own two NCE systems,  Digitrax and some where in storage I have the original lenz system back from 1980's.     The Digitrax system and NCE outputs  the same signal to the track.  Digitrax needs to be configured a lot more than the NCE but they are the same.    As I stated earlier, your problem of blowing the  lights and melt down is due to not setting the current limiting resistors properly.     I have the same rdc's light boards and have not had a melt down with either system period.    I did have to reconfigure and adjust the command station and boosters to output the proper voltage to the track.  When Kato became aware of the melting lighting units, they redesigned the boards to LEDs with the appropriate sized current limiting resistors.   By the way, the Kato DCC branded dcc unit is nothing but a re-badged Digitrax zephyr unit.
 
     If you are running ESU decoders only then you should have about 15 volts on the track.    They seem to be the happiest at that voltage level.    Size your current limiting resistors for that voltage level. and adjust the voltage output for that. Some of the ESU sound decoders will misbehave when the voltage levels get less than 15volts  a standard non sound decoder will have no problems.     

On the issue which system is better it really is one that boils down to personal preference.      They all have their quirks that you have to adapt to, nothing is perfect.     
The technology is changing at a rapid pace  ESU and Zimo's latest offerings are even more advanced than NCE or Digitrax.   LCC and Cbus systems are starting to crop up in the hobby world. Time will tell if these systems will replace the current DCC systems out there.  The only thing for sure is that technology is moving forward and as a consumer we have to make the decisions on what is best for ourselves.      Enjoy the hobby and be happy!     

[Greg Elmassian]

Petski: The nmra has lots on the DCC track voltage vs. scale, typical, max, etc.

Also what decoders should handle.

https://www.nmra.org/sites/default/files/standards/sandrp/pdf/s-9.1_electrical_standards_2006.pdf

[peteski]

Petski: The nmra has lots on the DCC track voltage vs. scale, typical, max, etc.

Also what decoders should handle.

https://www.nmra.org/sites/default/files/standards/sandrp/pdf/s-9.1_electrical_standards_2006.pdf

Thanks!  So for N scale it is 12-14V.

[cgw]

The problem with the NMRA standards is that they are voluntary.  Manufacturers do no have to abide by them.  There was a group of guys early on tried to get all the dcc manufactures to have the same protocol for the dccc decoders.   There was the Marklin/Motorola format, Trix Selectrix, Fleishman DCC, Arnold, Dynatrol, lenz, NCE, Wangrow System One, Hornby Zero, Zimo, CTX, and Digitrax  etc  and the only thing common with these manufactures  decoders was that they could only work with their own hardware.   People forget  the misery of early DCC.   Several of these systems have drifted off into the sunset and have disappeared from the landscape due to technical obsolescence.   Digitrax early success came from the fact that it could be configured to operate several of these other systems decoders fairly successfully.    The NMRA standards early on were skewed towards the Lenz protocols in DCC.   It was conjectured that  committee chairperson was  influenced by his wife who owned the Lenz distributorship (agency) in north America.  Lenz also let the NMRA have the intellectual property for the standard.  Others manufactures chose not to do that.   Over a period of time the DCC committee members were able to influence many of the manufacturers to standardize on one protocol for decoders.   NMRA committee started to issue conformance warrants to the standards and over a period of time the majority of the manufacturers began to adopt the standard.    Life was good!   A big thanks to the volunteers and the NMRA for driving this.  You now can chose several manufactures decoders and they would work with multiple systems.    Unfortunately, you could not interoperate the throttle busses  every manufacture decided not to standardize that portion of the hardware.     NCE claim to fame was the multitude of different throttle handhelds that you can get.   There was something for everyone.  Some of the throttles from the manufacturers required the user to get into the brains of the software coder to understand how to use them.   

The processors that many of the manufactures have standardized thier designs are starting to reach their end of life cycles.  This will drive more changes into the DCC landscape.      ESU and Zimo have deployed next generation processors in their product lines that allow for better sound processing, motor load control, and  additional functions.    With these advances we are now getting back into to the grey area of compatability.   The cv definitions are being changed due to the definitions of what they control.     

What everone has to realize that most of DCC equipment manufactures are really small companies that are operated on a shoestring budget.  They are owned and operated by passionate individuals who are model railroaders like the rest of us.  What I find facinating when I get to meet several of these folks is that they were ticked off over what was availible to them at the time and decided that they would impove upon it and ended up becoming the manufacturer themselves.   

[peteski]

NCE is actually a reincarnation of Wangrow System One.  A really good article about the NCE's history is : https://sites.google.com/site/markgurries/home/nce-info/nce-history  The entire website has lots of useful DCC info.

[OldEastRR]

Well, you can SAY the track voltage output between an NCE PowerCab and a Digitrax Zephyr are the same, but the markedly different light intensity of the identical car on different systems tells me that your assumption is not a fact. IF there was a way to adjust the Zephyr track voltage, I didn't see that mentioned in the instruction book. If it was some esoteric note in a big reference book or some sub-website for DT then sorry but that's just another strike against using DT. BTW, I haven't found anything in the NCE manual about adjusting track voltage, either. But then I don't have to.
I don't know where you got the idea that KATO changed the resistence on their RDC LED lightboards but I just got some new boards and the resistor value is the same as on my previous boards. I have to wire in the new boards so I'll find out later how they do.
And I'm not complaining about DCC --  it turns out my complaints were all because of the unfathomable quirks of the Digitrax system. I'm very very happy with DCC now because of NCE. I can easily change all the CVs I want to customize my engines now with minimum fuss. However, a friend who's very into DCC has told me that it is going to get very complex and more diverse very soon with the next generation of decoders and control systems -- so much so it will take special equipment and hard-wired computer connections to do anything beyond running the loco and blowing the horn. But all my locos will be equipped with today's decoders on today's system, so I don't anticipate having to sink back into a DCC swamp.
As for your use of DT, good luck and good sailing. Tho it may be working fine now, there might come a day when it turns on you and melts/shorts out your equipment -- like a pet dog that goes rogue and rips your face off.  Just sayin'....

[jdcolombo]

Different DCC systems output different voltages to the track.  Period.  I have observed this in person, measured with my Fluke 110 multimeter, dozens of times.  The difference often is as simple as a difference in the input transformer voltage.  In some cases, it is the result of specific designs, pots being changed inside a command station chassis, etc.  But I have seen it often enough that I don't take my N scale sound-equipped engines, which I've optimized for 11.5v track voltage, to other layouts.  They stay at home, where they work beautifully and don't blow the 16v tantalum caps I use for keep alive.

I have little doubt that the Zephyr was outputting more voltage to the track than the NCE system.  How much more, and why, we will likely never know, since you don't have the Zephyr any more.  But since all is well now, no big deal.

John C.