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What is the best way to run DC and DCC equipped locos on your layout?

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  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Wednesday, March 2, 2011 9:40 PM

 As for the burning out the motors thing - the other night was a work session on my friend's N scale layout, and he had just aquired at Atlas Trainmaster that does not yet have a decoder and he was runnign it around. This and all the threads where peopel are screamign to never use address 00, you'll fry your loco prompted me to ask him if he ever fried any of his - most of his locos are scratchbuilt or at least modified and he usually uses Kato motors in them, and he's been workign on this layotu and had a Super CHief system for 4-5 years now. And the answer - no, never fried a non-decoder loco, and he runs them all the time on address 00 until he gets a decoder installed - and on a small camelback with the motor int he tender there's not much room for a decoder, he ends up using the ultra micro ones like CT Electronik and now the new DX125 from Digitrax. But he's run many many locos on address 00 with absolutely NO problems.

 The ONLY motors that won't take it are coreless motors. There's no 'massive' armature to act as a heat sink and they tend to melt pretty quickly. But they also melt if used with a decoder that does not use supersonic or high frequency drive.

                          --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
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  • From: Seattle, Washington
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Posted by IVRW on Wednesday, March 2, 2011 6:53 PM

If you control your layout with DCC, you can run a DC locomotive by programing your digitrax system to address 00. I dont know if this works in conjunction with DCC locomotives, but assuming so, you can only run one DC locomotive at a time without power "Blocks"; basically a system where one power pack controls one small section of track, and no electrical sections overlap.

~G4

19 Years old, modeling the Cowlitz, Chehalis, and Cascade Railroad of Western Washington in 1927 in 6X6 feet.

  • Member since
    March 2007
  • From: South Carolina
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Posted by Train Modeler on Tuesday, February 15, 2011 8:58 PM

I did the DPDT, center off switch too.   But I found that having districts helps a lot even in DCC to cut the power to certain areas for a lot of reasons, such as diagnosing problems and letting the locos sit unpowered whether DCC or DC, etc.

So I feed my DPDT switch to a bank of switches for the districts.  

I also have a switch for the programming track(has to be highly visible) especially if more than you will operate.   Since this is in a yard I usually leave in center off position.

At one point I divided the layout up for a DCC portion and a DC portion.   It only took two switches and an additional couple of wire feeds.    This can of course cause issues if you run a loco over and bridge the two power types.    But in a year of operation, we never had a problem with that.

Richard

  • Member since
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  • From: Reading, PA
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Posted by rrinker on Tuesday, February 15, 2011 7:03 PM

 You have that backwards, those old big open frame motors can take the 'abuse' better than a modern more efficient motor. In fact it was using address 00 that I was able to get an old built but never run Bowser PRR T-1 with dual motors to finally loosen up. It wouldn;t break loose on either of the DC power packs I had, it would just short out. I put it on the layout and fired up the Zephyr in address 00 and finally it started to move, Ran it back and forth for a while and soon it was running pretty well.

 Coreless can motors will be pretty much INSTANTLY destroyed if set on DCC track, or if run with a decoder that does not use high frequency 'supersonic' drive.

 Friend of mine has what you need for mixing DC and DCC - a HUGE DPDT knife switch. No possible way for the DC side to touch the DCC side, only one power source will connected to the rails at a time so there is zero chance of frying anything. Not sure where he got it, he keeps it around as a conversation piece. A more normal size DPDT center-off toggle will work too.

                     --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    October 2004
  • From: Colorful Colorado
  • 8,639 posts
Posted by Texas Zepher on Monday, February 14, 2011 10:16 PM

Lateral-G
Out of curiosity what sort of damage can occur to the motor by running a square wave AC current thru it? (winding damage, overheating, etc)

Well, just think of how a demagnetizer works.   Put the magnet in an coil with an AC current running through it.   Sounds just like a non-turning motor with DCC running through it to me.    

You need to search out a few threads by Jeff Wimberly (about 4 years ago) where he took real HO locomotive motors and measured how long it took them to melt down or fail when subjected to a DCC current.  Here is one of them http://cs.trains.com/TRCCS/forums/t/105396.aspx

It took me about 30 seconds of listening to the buzz of a DC locomotive running on a DCC system to make me decide it was a really bad idea.

 

  • Member since
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  • From: Pa.
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Posted by DigitalGriffin on Monday, February 14, 2011 10:36 AM

Lateral-G

Out of curiosity what sort of damage can occur to the motor by running a square wave AC current thru it? (winding damage, overheating, etc)

Overheating them.  Same reason a AC current bulb will burn brighter than a DC current bulb of the same voltage.  It's because it runs hotter.

Don - Specializing in layout DC->DCC conversions

Modeling C&O transition era and steel industries There's Nothing Like Big Steam!

  • Member since
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  • From: O'Fallon, MO
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Posted by Lateral-G on Monday, February 14, 2011 10:16 AM

DigitalGriffin

WARNING:

Using address 0 is hard on your motors.  Especially if

1) They are non-can/high current motors

OR

2) You let them sit at speed step 0 for a long time. 

You risk burning out the motor because you are sending square wave AC current through a motor designed for DC.

 

Understood.

These are can motors installed.I have no intention of running open frame, high current draw motors.

I do not leave these analog locos idle on the powered track. Once they are done they are routed to the yard where the track voltage can be turned off with a toggle switch.

Out of curiosity what sort of damage can occur to the motor by running a square wave AC current thru it? (winding damage, overheating, etc)

 

 

 

  • Member since
    December 2004
  • From: Pa.
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Posted by DigitalGriffin on Monday, February 14, 2011 10:00 AM

WARNING:

Using address 0 is hard on your motors.  Especially if

1) They are non-can/high current motors

OR

2) You let them sit at speed step 0 for a long time. 

You risk burning out the motor because you are sending square wave AC current through a motor designed for DC.

Don - Specializing in layout DC->DCC conversions

Modeling C&O transition era and steel industries There's Nothing Like Big Steam!

  • Member since
    February 2008
  • From: O'Fallon, MO
  • 292 posts
Posted by Lateral-G on Monday, February 14, 2011 9:26 AM

I hooked up the Super Chief System this weekend. Works great!

I model HOn3 D&RGW and have several BS K-27's with DCC/sound. They work great right OOB and no need to program anything. I also have several HOn3 diesels custom made by a guy on ebay that are DCC ready but no decoders yet. I ran then to with the loco address as 00. They worked fine as well and the buzz from the motor was minimal. Excellent throttle response and slow speed operation. I even ran the DCC steamers and the analog diesel at the same time. No problems what so ever.

Per the Digitrax instructions I know not to leave them on the track when not in use.

I'm looking at some DCC decoders with sound from Soundtraxx for the diesels but at over $100 a pop and 4 locos to convert it may be a while.....

Hopefully in the next few days I'll have my new motor and decoder from LocoDoc for my WSM C-16 then I'll have some DCC brass going....

Thanks for all the replies!

 

-G-

 

 

 

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Posted by Hamltnblue on Saturday, February 12, 2011 10:54 PM

Once you have a couple of loco's changed over consider pulling the tirgger and converting. When you want tu use a loco make that the time to convert. 

Springfield PA

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  • From: Bedford, MA, USA
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Posted by MisterBeasley on Saturday, February 12, 2011 10:28 PM

I thought I would do that for a while, too, as I had a number of old DC engines that I figured would take some time to convert.  As it turned out, only one of the old engines was even functional after all those years in the attic.  However, as I bought new engines I tried running them in DC mode as Engine Zero before I bought decoders.

It taught me something.  You really want to put decoders in, as soon as possible.  Even though I could run these engines, I didn't.  (Very similar to buying sound engines, and finding that the non-sound engines became display pieces on sidings very quickly, actually.)

Running as Engine Zero doesn't get the engine to full speed, or even close.  It pokes along, and makes an annoying buzzing sound that reminds you more of an old Buck Rogers spaceship than a locomotive.  For the DC engines, you're running the track again.  Forward and reverse go back to being "clockwise" and "counter-clockwise" around the loop.  If you have auto-reversers, you'll find they don't work with DC engines.

You're going to find that you're already hooked on DCC.

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

  • Member since
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  • From: Westchester NY
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Posted by retsignalmtr on Saturday, February 12, 2011 4:59 PM

There are two ways to run DC locos on a DCC equiped layout.  Using a DPDT switch for each power district you can switch back and forth from DC to DCC. Or you can run the DC loco on DCC by using the address 0 on the DT400. You can even MU the loco with a decoder equiped loco although they will not be speed matched. Digitrax is one of the systems that allow you to run a DC loco with address 0.

DO NOT LEAVE THE DC LOCO SITTING ON DCC POWERED TRACK WHILE NOT RUNNING IT. The motor may overheat and be damaged and it may also creep along the track on its own.

  • Member since
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Posted by Stevert on Saturday, February 12, 2011 4:03 PM

Be sure you use a DPDT-center off, or other "break before make" switch.  You really don't want to take a chance of back-feeding DC into your DCC system's outputs.  The results of doing so are often a trip to the mother ship for repair...

  • Member since
    February 2008
  • From: O'Fallon, MO
  • 292 posts
Posted by Lateral-G on Saturday, February 12, 2011 11:56 AM

That's what I was thinking of as well...using a DPDT switch to transfer between the two.

I only have one power district (the entire layout) and no boosters or other DCC controlled equipment.

 

  • Member since
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  • From: Chamberlain, ME
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Posted by G Paine on Saturday, February 12, 2011 11:39 AM

I am in the same situation. What I did was connect the output of the DCC and my MRC Tech III to the outside connectors of a double pole double throw switch (DPDT) and connect the center pole of the switch to the layout. That was you can seelect which power source you want to use.

This ONLY works if:

  • You have only ONE power district on your layout. If you have another DCC booster, that part of the layout will not get power and you could damage the booster.
  • You have no other DCC components connetced to the layout like PowerShields, auto reversers, signals or turnouts controlled by DCC, etc. These components can be fried if connected to straight DC power.

 

George In Midcoast Maine, 'bout halfway up the Rockland branch 

  • Member since
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  • From: O'Fallon, MO
  • 292 posts
What is the best way to run DC and DCC equipped locos on your layout?
Posted by Lateral-G on Saturday, February 12, 2011 11:20 AM

I have a mix of DC and DCC locos.

I have both an MRC Control Master 20 DC transformer and a DigiTrax Super Chief system. I can use the Control Master as a power supply for the DigiTrax.

Right now I can't afford to equip all my locos with decoders and sound but I would like to be able to run them when I want.

My layout is wired for straight DC/DCC with no blocks. I did this with the intention of the future state of being completely DCC. However, until I reach that stage I'd like to still use all the locos on my roster and not have to mothball them until I can afford to upgrade.

What is the best solution in a situation like this?

-G-

 

 

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