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CONVERTING A DC LAYOUT WITH BLOCKS TO DCC

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  • Member since
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  • From: Reading, PA
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Posted by rrinker on Friday, June 28, 2019 10:06 AM

 Yes, with 2 switches, and both DC and DCC connected, it's too easy to accidently turn on BOTH switches and that will absolutely fry something - probably the DCC system. If you want to be able to use both, the best way is a mechanical means of preventing both from being connected. For example, a 2 pin connector ont he layout. ANd matching 2 pin plugs connected to the DC power pack, and the DCC system. Only one or the other can be physically plugged in at a time, it's not possible to have both connected no matter how absent minded you get. A big old knife switch mentioned in the other thread is a good option - also not possible to have both systems connected. A DPDT center off (must be center off - that gives you an electrically dead option in the middle) switch works fine. It's either set to DC, set to DCC< or completely off, there's no way for the DC to touch DCC - that is the end goal, the two must NEVER come together, deliberately or accidently. Either run ALL DC, or ALL DCC. Never a mix. 

                                 --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: Northern CA Bay Area
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Posted by cuyama on Friday, June 28, 2019 2:08 PM

rrinker
Yes, with 2 switches, and both DC and DCC connected, it's too easy to accidently turn on BOTH switches and that will absolutely fry something - probably the DCC system.

+1

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Posted by maxman on Saturday, June 29, 2019 10:54 AM

In my opinion either go DCC and remove the DC power option, or stay with DC since most DCC locos will run (maybe not as well) on DC.

This business of going back and forth between DCC and DC sounds like a problem waiting to happen.  Reminds me of the guy who took such large steps to save his $20 shoes that he split his $50 pants.

  • Member since
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  • From: Bakersfield, CA 93308
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Posted by RR_Mel on Saturday, June 29, 2019 12:43 PM

Wired properly one can run dual mode, DC or DCC.  I’ve been running dual mode since I bought my DCC Prodigy in 2006 and I’ve never had any problems.  My great grand kids can run either mode without my help.  
 
I keep my locomotives in a display shelf unit with two sections labeled DC on the lower shelves and DCC on the upper shelves.  Once introduced to my control panel anyone can run either mode easily.
 
Even my 5 year old great grand daughter knows if she picks a DC locomotive to run she turns on the DC power pack and she’s good to go.
 
I interlocked the DC power pack from the DCC controller using a DPDT relay.  I wired the relay coil to the accessory output on the DC power pack.  When the DC power pack is turned on the relay switches the track power from the DCC controller to the DC power pack.
 
A DPDT switch would have worked as good as the relay but I prefer the automatic power transfer method.  I have enough toggles on my control panel with out adding more.  
 
When one has less than 20 DCC decoders and over 70 locomotives dual mode is a must have if one wants to run all of them at one time or another. 
 
 
Mel
 
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
 
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Posted by maxman on Saturday, June 29, 2019 3:01 PM

RR_Mel
I’ve been running dual mode since I bought my DCC Prodigy in 2006 and I’ve never had any problems.

https://i.pinimg.com/originals/6a/12/3e/6a123ef6c6f1aa6670a078f1a0c982ae.jpg

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Posted by ATLANTIC CENTRAL on Saturday, June 29, 2019 4:47 PM

maxman

In my opinion either go DCC and remove the DC power option, or stay with DC since most DCC locos will run (maybe not as well) on DC.

This business of going back and forth between DCC and DC sounds like a problem waiting to happen.  Reminds me of the guy who took such large steps to save his $20 shoes that he split his $50 pants.

 

Most dual mode decoders won't run at all on the DC throttles I use..........

Sheldon

    

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Posted by maxman on Saturday, June 29, 2019 8:20 PM

ATLANTIC CENTRAL
Most dual mode decoders won't run at all on the DC throttles I use..........

Most DC users don't use the throttles you use...........

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Posted by ATLANTIC CENTRAL on Saturday, June 29, 2019 8:48 PM

maxman

 

 
ATLANTIC CENTRAL
Most dual mode decoders won't run at all on the DC throttles I use..........

 

Most DC users don't use the throttles you use...........

 

And you have taken that survey?

They may not use the Aristo throttles, but a great many who have stayed with DC use advanced throttles with pulse width modulated motor control, or other forms of pulse power, that are not compatible with dual mode decoders.

Sheldon

    

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Posted by SeeYou190 on Saturday, June 29, 2019 9:14 PM

rrinker
A DPDT center off (must be center off - that gives you an electrically dead option in the middle) switch works fine. It's either set to DC, set to DCC< or completely off, there's no way for the DC to touch DCC

.

After reading this, I think an Onan OTPC transfer switch is the only safe switching option. They are set up for dual inputs, 480 volt three phase from both Utility Line and Stand By Generator. It is impossible for the output to be connecteed to both at once.

.

The built in lockout mechanism is rated for transfering loads at full power, so durability will not be an issue.

.

If it works for office buiding line power, it should be able to handle DC and DCC safely.

.

  

.

-Kevin (tounge in cheek)

.

Living the dream.

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Posted by ATLANTIC CENTRAL on Saturday, June 29, 2019 9:16 PM

I think Mel has a great approach for those not wanting to convert their whole fleet of locos to DCC.

Apart from that, I agree, I would be all in one way or the other.

That's why I remove those pesky decoders.

Back in the day, those motion only Bachmann decoders sold real well on Ebay. I often sold them in three packs for about $40.00

Sheldon

 

    

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Posted by ATLANTIC CENTRAL on Saturday, June 29, 2019 9:22 PM

Kevin,

You use Troller power packs right? Have you ever tried to run a dual mode decoder DCC loco with one of those?

I suspect the result would not be good.

Dr Wayne uses pulse power throttles, I use pulse power throttles, maybe we need a survey........

Sheldon

    

  • Member since
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  • From: Southern Florida Gulf Coast
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Posted by SeeYou190 on Saturday, June 29, 2019 9:26 PM

My only dual mode decoder works with a Kato power pack just fine.

.

I only have one locomotive with a dual mode decoder. I have never tried it on a Troller Autopulse power pack because I fear damaging it, and I accidentally glued the tender shell shut.

.

If I damage the decoder, I am up a creek.

.

-Kevin

.

Living the dream.

  • Member since
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  • From: Maryland
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Posted by ATLANTIC CENTRAL on Saturday, June 29, 2019 10:08 PM

SeeYou190

My only dual mode decoder works with a Kato power pack just fine.

.

I only have one locomotive with a dual mode decoder. I have never tried it on a Troller Autopulse power pack because I fear damaging it, and I accidentally glued the tender shell shut.

.

If I damage the decoder, I am up a creek.

.

-Kevin

.

 

Well, I have to admit, I've never touched a KATO power pack........

Sheldon

    

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Posted by maxman on Saturday, June 29, 2019 10:43 PM

ATLANTIC CENTRAL
And you have taken that survey?

No I haven't.  But I'm not sure I see the point of doing so.  The population of people who would need to be surveyed would be those who would wish to use DCC locos with sound on either DC or DCC; or want to go back and forth between DC and DCC (which I think was the original question, but I'd have to go back and look).

I don't think that surveying people who are DC only, have no interest in DCC, or remove DCC decoders has much relevance to the swapping back and forth thing.

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Posted by maxman on Saturday, June 29, 2019 10:51 PM

duplicate

  • Member since
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Posted by ATLANTIC CENTRAL on Saturday, June 29, 2019 10:55 PM

maxman

 

 
ATLANTIC CENTRAL
And you have taken that survey?

 

No I haven't.  But I'm not sure I see the point of doing so.  The population of people who would need to be surveyed would be those who would wish to use DCC locos with sound on either DC or DCC; or want to go back and forth between DC and DCC (which I think was the original question, but I'd have to go back and look).

I don't think that surveying people who are DC only, have no interest in DCC, or remove DCC decoders has much relevance to the swapping back and forth thing.

 

But it does have relevance to your suggestion of running DCC locos on DC?

Which is particularly troublesome with sound locos, where the locos do not even move until half throttle, even with pure DC throttles that are friendly to dual mode decoders.

Sheldon

    

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Posted by maxman on Saturday, June 29, 2019 11:14 PM

ATLANTIC CENTRAL
But it does have relevance to your suggestion of running DCC locos on DC?

No, not exactly.  What I typed was:

"In my opinion either go DCC and remove the DC power option, or stay with DC since most DCC locos will run (maybe not as well) on DC."

And that was to address the folks who want to go back and forth between DC and DCC.  I would sort of think that those individuals who are asking the "how do I go both ways" question are not using the more sophistocated DC power sources, but I could be mistaken

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Posted by rrinker on Sunday, June 30, 2019 1:11 PM

SeeYou190

 

 
rrinker
A DPDT center off (must be center off - that gives you an electrically dead option in the middle) switch works fine. It's either set to DC, set to DCC< or completely off, there's no way for the DC to touch DCC

 

.

After reading this, I think an Onan OTPC transfer switch is the only safe switching option. They are set up for dual inputs, 480 volt three phase from both Utility Line and Stand By Generator. It is impossible for the output to be connecteed to both at once.

.

The built in lockout mechanism is rated for transfering loads at full power, so durability will not be an issue.

.

If it works for office buiding line power, it should be able to handle DC and DCC safely.

.

  

.

-Kevin (tounge in cheek)

.

 

 Well, there would definitely be no issued with power loss due to contact resistance. ANd should one EVER wear out, there is a spare contact on both sides.

                               --Randy


Modeling the Reading Railroad in the 1950's

 

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

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