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Engine performance: DC vs DCC

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  • Member since
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  • From: Western, MA
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Posted by richg1998 on Sunday, October 16, 2011 2:41 PM

mwcohio

I really appreciate all of your replies to my question! Many of you are wondering why I would go DCC and not have a DCC engine. I have 7 engines and am planning on converting them all to DCC. I didnt see any sense in spending money on a DCC engine when I can convert my existing ones much cheaper. Thanks again for the replies! Mark.

Very nice to see your response. Many never come back and explain what sometimes seems to be a mystery.

Make sure you ask here about individual loco conversions in case you have not done this before. Some may have been down that path or a similar path. Good Non sound decoders are around $20.00 each. Many here can suggest good on line sources. I usually prefer Litchfield Station.

Rich

 

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.

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Posted by mwcohio on Sunday, October 16, 2011 2:09 PM

I really appreciate all of your replies to my question! Many of you are wondering why I would go DCC and not have a DCC engine. I have 7 engines and am planning on converting them all to DCC. I didnt see any sense in spending money on a DCC engine when I can convert my existing ones much cheaper. Thanks again for the replies! Mark.

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  • From: Western, MA
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Posted by richg1998 on Sunday, October 16, 2011 10:40 AM

Lake

Why would you go DCC, and I have a Digitrax system and love it, and not have at least one DCC engine?Huh?

What we are all saying is, do DCC or not do DCC, there is no I will kind of try DCC.Hmm

I think Yoda said about the same.

Rich

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.

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  • From: Clearlake, California. USA
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Posted by Lake on Friday, October 14, 2011 8:32 PM

Why would you go DCC, and I have a Digitrax system and love it, and not have at least one DCC engine?Huh?

What we are all saying is, do DCC or not do DCC, there is no I will kind of try DCC.Hmm

Ken G Price   My N-Scale Layout

Digitrax Super Empire Builder Radio System. South Valley Texas Railroad. SVTRR

N-Scale out west. 1996-1998 or so! UP, SP, Missouri Pacific, C&NW.

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  • From: City of Québec,Canada
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Posted by Jacktal on Friday, October 14, 2011 3:48 PM

The only safe way to operate your DC locos on your layout is to have the layout DC powered.If everything goes well (all bugs ironed out) then switching to DCC later will be a piece of cake.Simply substitute your DC controller with the DCC command station.However,you will have to control polarities manually,called block control,wich involves switches and other controls that will become useless when you switch to DCC.

And keep in mind that you can't install polarity reversing modules (AR-1 and the likes) or a PM-42 until you are full DCC.These items won't like DC either.In short,since you know you want DCC,you might as well go DCC right away...you'll save the extra switches and the more complex wiring DC requires.

  • Member since
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  • From: Western, MA
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Posted by richg1998 on Friday, October 14, 2011 2:52 PM

bigray1964

but if you isolate the rail joiners for dc loco's you can run dc and dcc is this correct?

You can and some do but you better know what you are doing.

Rich

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.

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  • From: City of Québec,Canada
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Posted by Jacktal on Friday, October 14, 2011 2:51 PM

Although not an impossible thing to do for skilled technicians,it is HIGHLY discouraged.Isolating part of a layout to allow DC to be run at the same time as DCC has been discussed many times on this and other forums and the resulting opinions are unanimous...a definite NO NO.

It's only a matter of time that a DC(or DCC) loco mistakingly jumps the gap between DC and DCC power and believe me,if you forget to avoid bridging the gap,you certainly won't forget the sweet smell of cooked electronics.

  • Member since
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  • From: Western, MA
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Posted by richg1998 on Friday, October 14, 2011 2:50 PM

  If a DC loco crosses into a DCC section and the DCC controller is on, the DCC system ca be smoked Happened in our cub with a NCE Power Pro and has happened so some others.

We had 14 blocks, four DC throttles and used on DC throttle connector for our DCC  and attempted to cheat and did not get away with it. We went strictly DCC.

Never, ever forget about Murphy. This issue has been discussed, Ad nauseam here.

Rich


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.

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Posted by bigray1964 on Friday, October 14, 2011 2:37 PM

but if you isolate the rail joiners for dc loco's you can run dc and dcc is this correct?

  • Member since
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  • From: Western, MA
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Posted by richg1998 on Friday, October 14, 2011 2:30 PM

Below is a link with photos of zero bit stretching. Notice all the pulses outside the zero bit. Those keep the armature vibrating and how much the armature vibrates can depend on the motor quality.

Even if the throttle is a zero, those pulses are still there. Those pulses contain the info to operate a decoder.

http://members.shaw.ca/sask.rail/dcc/DCC-waveforms/DCC_waveforms.html

Rich

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.

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Posted by fwright on Friday, October 14, 2011 1:36 PM

Pheobe Vet gave you the short answer.  Zero stretching to enable decoderless locomotives to run on DCC should be viewed as a temporary substitute until decoders can be installed.  And decoderless locomotives should not be allowed to stand still with DCC power on the track to avoid motor overheating and eventual destruction.

Another way of looking at things - the better DC throttles employ a little more circuitry to improve locomotive performance.  In DCC, this improved throttle is located in the decoder.  So if you want to improve performance on DCC, you install a decoder with a quality motor drive circuit.

Fred W

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Posted by Phoebe Vet on Friday, October 14, 2011 6:12 AM

Yes.

DC running on a DCC layout uses zero stretching.  It is actually running on asymetric AC.  That makes them noisy and reduces their performance.

http://loystoys.com/info/how-dcc-works.html 

Dave

Lackawanna Route of the Phoebe Snow

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Engine performance: DC vs DCC
Posted by mwcohio on Friday, October 14, 2011 1:20 AM

Im working on a new layout and bought my first DCC system to run it (Digitrax). I dropped feeders every 3 feet on my 65' around the room layout. I dont have any Engines converted to DCC yet but I knew that I could use my DCC controller to run my DC Engines. What Im experiencing is that my Engines run slow and sluggish all around the layout, but when I use my old DC controller they run just fine. Will my Engines run better with the DCC controller when I convert them to DCC? Mark.

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