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Discussion Starter #1
I just purchased a NCE Powercab and a couple of Dcc locomotives. They run much slower on Dcc than dc. Is there any way to turn up the speed ? I have HO scale.
 

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There *may* be, there are some speed increment settings, but I don't play with them myself. Do you have all the programming information for the locos? You'll need that. Post what locos and/or decoders you have.
 

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As Tom C said, there may be a CV for top speed. In general, I have found DCC
does run a little slower than DC. Your track voltage on DCC is lower than what a DC transformer can put out.
 

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Locomotives running DCC will still run at a realistic scale speed. If you are used to trains running around a loop in the blink of an eye like toy train O scale, HO scale speed is something to get used to. It does not look fast to the eye.

If they are covering 36" of track in about 4.2 seconds they are traveling at a scale speed of around 41 MPH give or take.


But yes, there are many settings in the CV's to control many motor speed parameters. Be careful in there. They are easy to screw up if you don't understand what you are changing.
 

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A DC power pack at max puts out around 16 Volts; track power for most DCC systems is around 14V, so you'll never reach the same max speed with DCC. However, as MichaelE points out, max speed with DC is usually much faster than the full sized equivalents ever run. Most locos with factory-installed decoders come programmed to run at realistic speeds, and this may look surprisingly slow to you.

Look at the documentation that came with your decoders. There should be a list of Configuration Variables (CV's) and what they do. You're looking to set the one governing max speed (or max voltage) to it's highest setting. The specifics on how to do this vary for different DCC systems and decoders.

If all else fails, setting CV8 to a value of 8 will reset most decoders to their factory defaults, so you can get back to a known good condition if you really mess things up.
 

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DCC isn't going to run your train at slot car speeds.
One way to ensure you are getting top speed out of your decoder is to set CV 5 to 255. That is the top end speed command of the decoder, not the locomotive speed. CV 6 will let you adjust the mid range speed, about 125.
 

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Discussion Starter #8
After operating these for a period of time,I am becoming accustomed to the speed. I am not experienced enough yet to start changing advanced parameters. Thanks for everyone's help.
 

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OP wrote:
"I am not experienced enough yet to start changing advanced parameters."

There's not much to this -- at least at a basic level. (at least on the Roco z21 system that I use)

One thing you should do is before you change a particular CV setting, to write down what the current one is. That way, makes it much easier to "go back".
 

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J.Albert is right, nothing to it.

If you don't have a isolated programming track, take all other locos off the track, then on the powercab press prog/esc, select to use programming track, not main track, then select CV. Enter the CV to change and it will show you the existing value, then you can enter the new value. If you mess something up, just program CV 8, to the value of 8 to reset to default. Lather rinse repeat.

BTW, you don't need to enter all 3 digits. for CV 8, just enter 8, not 008. It will work either way, it's just not necessary.
 

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OP wrote:
"I am not experienced enough yet to start changing advanced parameters."

There's not much to this -- at least at a basic level. (at least on the Roco z21 system that I use)

One thing you should do is before you change a particular CV setting, to write down what the current one is. That way, makes it much easier to "go back".
This reply is spot on. Changing the speed settings on a decoder is DCC 101. When you set up a decoder for the first time (that is, program the loco number), MRC systems ask you to also enter numbers for start voltage, max voltage, and mid-range. You can bypass these inputs if you want to, but since they're included in the basic set-up process, it's pretty obvious that those CV's are essential basic knowledge.

OTOH, you may not THINK you're experienced enough for "advanced topics"... but if you don't push yourself beyond what you already know, how will you learn and grow?
 

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Actually, CV programming is slightly more advanced than turning the headlight on or off.
 

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One other thing, which I was just reminded of. When starting with a new loco it might be best to reset it to default before you start. That way you are sure any CV you want to see the original value is actually reset to default.

I was just programming a new loco I got, and the CV's weren't matching what the documentation showed. I reset it to default and then went to look up the document on line. After I verified I had the up-to-date document I went back, and after I reset it to default all the CVs matched the document. So, just reset it before you begin so you are on a level playing field.
 

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Tom's advice has long been given by member Randy Rinker on another forum. ANY TIME you get a 'new' locomotive into your hands, be it gently used on eBay or brand new from the importer, you should first do a CV8 =8 reset or whatever the process is to get to factory defaults. That renders what you have a known quantity.
 

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I just purchased a NCE Powercab and a couple of Dcc locomotives. They run much slower on Dcc than dc. Is there any way to turn up the speed ? I have HO scale.
If they conform voluntarily to NMRA standards, there are set voltages that each DCC system should apply to its outputs...BASED ON the scale. Different scales have different needs due to mass and resistances, so their voltages vary commensurately.

But, there are decoders, and decoders also vary. What they are asked to do varies, depending on the needs and decoder selected. But, they do things, and that takes energy. So the decoder gets all the power first, and then divvies it up to components in the locomotive, including lighting, drive mechanism, and sound system. This leaves the outputs for the motor reduced some from what the decoder needs for its own sake, and then what the lights and amplifier and speaker each need to do their bits. DC voltage just has to run a light and a motor.

Adjusting your drive to get the most out of the voltage and amperage available to it has been ably covered by the other responders.
 

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With the NCE Powercab you can program CVs on the Main.
Absolutely. Someone else suggested to make note of the original setting before changing it, and you need to do that on a programming track. Programming on the main won't read the existing value.
 

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Discussion Starter #18
Slow locos

I am using a NCE Powercab with Mantua locos. I don't know how to check decoder information, what a cv is or how to locate them. I appreciate all the feedback as I have only been into this for a couple of weeks.
 

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I posted this already, but to read the CV value you need to set it to programming track, not main. That's why you need to be sure you remove all other locos unless you have an isolated programming track.

Press prog/exc, toggle through the options to where you can select 'programming track', then select CV. You then enter the CV# and it will read the existing value. You can then change the value or just press enter to keep the existing value without changing it.
 

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You need to push "prog/esc" 4 times to get to programming track. Then push enter. You will see a menu of options displayed. Push 2 to get to the CV programming page. Once on that page you push the number of the CV you wish to change. The PowerCab will read the value currently stored in the decoder and display it. Be patient, it may take a litle bit to read it back. Write down the current value so you can reset if you desire. To change the maximum possible top speed, enter 5 as the number of the CV you wish to change. Once the PowerCab has read back the current value, push 255, then enter. Pushing the "prog/esc" key takes you out of programming mode and back into operations mode. There really is nothing to fear about the process. The PowerCab makes it so easy, even I can do it! :)
 
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