DCC, DC, etc.

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M

MitchyG

the new guy
What is the difference betweeen DCC, DC, and the others layouts. I think it has something to do with the type of power / current/ voltage. Am I right? Which is better? Thanks.

P.S. Why is everyone copying my Question mark thing?!?!?!
 
MitchyG said:
What is the difference betweeen DCC, DC, and the others layouts. I think it has something to do with the type of power / current/ voltage. Am I right? Which is better? Thanks.
Click to expand...

DC is just that, Direct Current. With it you run one loco or set of locos in one block at any one time and they will all move in the same direction at pretty much the same speed.

DCC is Digital Command Control. It's direct current with an AC component that carries computer commands that are received by decoders in the locos. With it you can a number of locos in any one block at any given time. The locos can move in different directions relative to each other and at different speeds if you so desire. This is impossible to do with DC. What's more only the locos that you want to move will move. If there are three decoder equipped locos in the block and you want one to move while the others stay put you just punch in the address of that loco and it will do whatever is commanded of it while the others sit idle. You can control any number (as many as the system will allow) of locos at once and completely independent of each other or they can move together in consist.
 


For N. American HO style trains with two rails and DC, the fact is that they are all DC...even the DCC decoder-equipped locomotives. It is just that when a layout has DCC operating the trains, the decoder rectifies the current to pulsed DC and assigns the voltage according to its programming to the motor leads.

In other words, the locomotives all have DC can motors in them, and that is what they need to turn...DC current. On a DCC layout, the decoder receives full voltage, constant voltage, from the rails, except that the power has a super-imposed digital signal that gives the decoder its instructions second-by-second.

As Jeff so aptly pointed out, if you have a length of rail in pairs receiving only DC current, whatever motors are getting the current will turn in the same direction. So, even if you have two locomotives with one facing away from the other, when you apply power to DC rails both engines will chase each other. It may not be the precise same speed due to assembly problems, or maybe even gearing designs, but they will both move in the same direction. Only an internal polarity switch would permit the two to move apart, and I don't think you'll find any/many HO engines with that capability.

With DCC, you tell the decoder to move the engine, and in which direction. The decoder reads the digital command in the signal imposed on the current, and does what it is told. So, on the same powered length of track, two engines will behave differently as commanded. Quite realistic in my view.

-Crandell
 
Some DCC systems allow you to run a DC loco (no decoder) on address 0. The NCE system won't do it. The Digitrax system will but the loco will be making an electronic screech the whole time it's on a powered track. Under no circumstances must it be allowed to sit idle for any period of time while it's on the powered track.
 
I recently got an old-but-new bachman switcher. It goes, but very slowly and making an awful screetching noise-not an electronic screetch. It was running on a DC loop. do you think it would have anything to do with a DC/DCC issue? if not, what's wrong?
 
If it's a DC loco running on DC current then I'd say it has a bad bearing. I've had several over the years that did that and had to remotor them. Two were Athearn and one was Bachmann. I also have a Proto 2000 GP38-2 that did that when I got it. I picked it up used as a gift from a friend. It's problem was a bad bearing in the front truck. I simply changed the whole truck out as that was easier than disassembling the truck and replacing the offending part. In your case I would say consider the replacement cost of the entire loco then consider whether it would be cheaper to fix it or to replace the entire loco. Most HO Scale DC Bachmann switchers today go for between $30 to $50 new.
 


Not bad. That's a bit less than half of what Bachmann wants for it. Before you start thinking about dumping money into it you need to consider that the pickups on the 0-6-0 aren't very good and it doesn't pull much. On an upgrade it'll pull very little. Now to the EZ-Command. You can't program with it other than setting the address and direction of travel and turning the light on and off.
 
well. I guess I can't use that, because I plan to have about 7 locomoties.
any suggestions on where to get a fairly cheap DCC system that can opperate maybe a dozen engines?
 
This is about the best price I've seen on the NCE Power Cab.
http://circlechobby.com/prodM/NCE25.HTM
It says it's a spring 2010 sale, so call and confirm the price.
The EZ Command will control up to 9 locomotives, just not all at once. If you plan to have 7 locomotives available then the EZ Command will handle that. You could probably actually run 3 at at time. But if something goes haywire in one of the decoders, the EZ Command will not allow you to program individual control values for the decoders, or reset the decoder to factory values. Just something to be aware of.
 


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