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Turning off DC in a DCC loco

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  • Member since
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  • From: Sierra Vista, Arizona
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Posted by cacole on Tuesday, April 21, 2015 10:34 AM

True, BUT, on a large club layout using an NCE PowerHouse Pro, you soon run into problems with the system using numbers under 128 for consist addresses in the main command station memory and trying to run a single locomotive that might have the same short address if the consist is on the track, can cause some very unpredictable results.

 

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Posted by CSX Robert on Monday, April 20, 2015 10:10 PM

cacole

 

 
Blind Bruce

I calculate 34 as my CV29 . I am still confused about ticking the long address box. Two losoc I have are addresses 121 and 312. Are they both long?

 

 

 
It depends on your DCC system.  An NCE PowerHouse Pro or PowerCab considers any number under 128 to be a short address, and uses these numbers for consisting purposes.
 

Actually, on NCE an address less than 128 can be a primary ("short" or "2-digit" ) address OR an extended ("long" or "4-digit") address.  If you use advanced consisting, then it is wise to use extended addresses below 128 so that you don't have overlap with your consists, but NCE does allow primary engine addresses below 128.

 

On Digitrax, all addresses below 128 are primary, and on Lenz, all addresses below 100 are primary.

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  • From: Bedford, MA, USA
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Posted by MisterBeasley on Monday, April 20, 2015 4:54 PM

richhotrain
To feed a man a fish and satisfy him for a day or to teach a man how to fish and satisfy him for life.

Feed a man a fish and he will eat for a day.  Teach a man to fish and he will sit in a boat and drink beer for the rest of his life.

Thus, teaching a man to fish detracts from layout time.

It takes an iron man to play with a toy iron horse. 

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Posted by richhotrain on Monday, April 20, 2015 2:43 PM

Under the Maxman Theory of Brevity, only the first sentence of the following quote was necessary.  The rest of the explanation was superfluous:

maxman

Bruce:  When you addressed the 121 loco, you should have entered the long address as 0121.  The NCE systems treat addresses from 1 to 127 as long addresses if you remember to enter them with zeros in front, for example 0100, not 100.

You can figure out how you addressed the 121 easily.  When you select loco enter 121.  If the loco runs you have it running on the short address.  If you enter 0121 and it runs, then it is running on the long address.

Wink

Rich

Alton Junction

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Posted by maxman on Monday, April 20, 2015 2:01 PM

richhotrain

maxman, which is better?

To feed a man a fish and satisfy him for a day or to teach a man how to fish and satisfy him for life.

Rich

 

Given the nature of the question, the one fish would be satisfactory and more than adequate.  Especially if he doesn't happen to like fish.

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Posted by richhotrain on Monday, April 20, 2015 1:18 PM

maxman, which is better?

To feed a man a fish and satisfy him for a day or to teach a man how to fish and satisfy him for life.

Rich

Alton Junction

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Posted by maxman on Monday, April 20, 2015 12:22 PM

Well, all of that stuff above is nice to know, but just adds to unnecessary confusion when all that is asked for is the answer, not the derivation of the answer.  The calculator takes care of all of it it one only wants the answer.

Besides, it didn't answer his add on question concerning whether or not his loco 121 was operating on a short or long address.

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Posted by richhotrain on Monday, April 20, 2015 12:03 PM

To add to the fun, consider CV29=4.

That would mean that DC operation is permitted, and the loco would run forward on its short address, using 14 speed steps.

Rich

Alton Junction

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Posted by richhotrain on Monday, April 20, 2015 11:53 AM

DC operation has a decimal value of 4 in CV 29.

CV29 is built as a binary numbering system (1 2 4 8 16 32 64 128), so each value is unique.  

For example, the value 34 can only be a combination of 2 (28/128 speed steps) and 32 (long loco address).  For DC operation, the value must have 4 added to it. Thus, the value of 38 would include DC operation.

If CV29 were set to run a loco in reverse, the value would be 35.  In that case, to permit DC operation, the value would have to 39.

Rich

Alton Junction

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Posted by Jacktal on Monday, April 20, 2015 11:32 AM

With CV29=34,DC operation is already "off".

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Posted by maxman on Monday, April 20, 2015 10:38 AM

cacole

 

 
Blind Bruce

I calculate 34 as my CV29 . I am still confused about ticking the long address box. Two losoc I have are addresses 121 and 312. Are they both long?

 

 

 
It depends on your DCC system.  An NCE PowerHouse Pro or PowerCab considers any number under 128 to be a short address, and uses these numbers for consisting purposes.
 

Bruce:  When you addressed the 121 loco, you should have entered the long address as 0121.  The NCE systems treat addresses from 1 to 127 as long addresses if you remember to enter them with zeros in front, for example 0100, not 100.

You can figure out how you addressed the 121 easily.  When you select loco enter 121.  If the loco runs you have it running on the short address.  If you enter 0121 and it runs, then it is running on the long address.

  • Member since
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Posted by cacole on Monday, April 20, 2015 10:17 AM

Blind Bruce

I calculate 34 as my CV29 . I am still confused about ticking the long address box. Two losoc I have are addresses 121 and 312. Are they both long?

 

 
It depends on your DCC system.  An NCE PowerHouse Pro or PowerCab considers any number under 128 to be a short address, and uses these numbers for consisting purposes.
  • Member since
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Posted by Blind Bruce on Monday, April 20, 2015 10:03 AM

I calculate 34 as my CV29 . I am still confused about ticking the long address box. Two losoc I have are addresses 121 and 312. Are they both long?

73

Bruce in the Peg

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Posted by maxman on Monday, April 20, 2015 9:23 AM

Bruce:  here is a link to a CV calculator: http://www.2mm.org.uk/articles/cv29%20calculator.htm

All you have to do is check the boxes that you want activated, or not activated in the case of DC operation, and it will calculate a CV 29 value.  Then you can just set CV 29 to that number.

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Posted by mlehman on Monday, April 20, 2015 9:18 AM

I'm pretty sure its always CV 29. Then things get complicated. NCE simply states it's bit 2 and the value is 0. Soundtraxx offers a whole page (page 16 of the steam tsunami users guide for instance) of values for CV 29 and there are multiple instances in the list where analog operation can be enabled or diabled. I suspect it's still bit 2 at 0, but with a lot more going on in CV 29.

Since the value of analog enabled is 1, I think if you simply reduce the value of CV 29 by 1 it will disable it. However, if you're not sure it's on, subtracting 1 could end up enabling it, depending on what other vlues you have in CV29.

Mike Lehman

Urbana, IL

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Turning off DC in a DCC loco
Posted by Blind Bruce on Monday, April 20, 2015 8:48 AM

I want to check that the DC function is turned off in all my locos. Is there a standard NMRA CV for this or do I need to look up each decoder function?

73

Bruce in the Peg

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