DCC Performance

[BobZ]

I am converting to DCC from DC. I recently purchased 4 DCC Equipped Spectrum
2-8-0. I also have 1 remaining DC engine. I test ran the new Spectrums and they seemed to run sluggish compared to the DC. They were running on a regular DC (not DCC) test track oval 150" in length for 5 laps. The DCC engines averaged 17.46 secs to 18.89 secs per lap. The DC engine did the same oval in 8.84 secs average per lap. All engines are brand new and were 'broken in' as advised by Bachmann. Is this normal under these conditions?   

[skipgear]

A DCC loco on DC requires about 4-5V just to start up the electronics in the loco. You lose that voltage to power the decoder.

The Spectrum Bachmann 2-8-0 is geared very slow anyhow so voltage changes are very evident in its top speed. Running on a proper 12V DCC system, they will top out around 60-70 Scale MPH which is all the loco would see in real life.

[Ken G Price]

My opinion on this subject is:
The advantage of DCC over DC is that you can have more control over the speeds. Real engines do not just take off and hit fell speed in seconds.
Unless you want to run them as if they are slot cars, and you may, for the first 6 to 8 seconds you will slowly increase speed just like the real thing.
The is especially true of steam engines. 
As Tony stated most engines by most of the manufactures are geared so in DCC they run slower and more realistic.

[BobZ]

That explains it. Thanks.

[GoCanes]

So, a DCC loco still uses it's decoder and DCC stuff even when it's on a DC only track? 

What about DCC ready locos? Do they need more volts because of their DCC stuff, when it's on DC only track? (or does it only apply to actual, decoder installed DCC locos?)

[poliss]

The 'ready' in DCC Ready means it's ready to have it's light board removed and then replaced with a DCC Decoder board. Until that's done, it's just a DC loco.
In some British locos there may be a socket or solder points for a DCC decoder to be fitted.

[Ken G Price]

So, a DCC loco still uses it's decoder and DCC stuff even when it's on a DC only track? 

What about DCC ready locos? Do they need more volts because of their DCC stuff, when it's on DC only track? (or does it only apply to actual, decoder installed DCC locos?)

Poliss stated what DCC ready means.
As for the DCC when using DC. (And I hope this makes sense)
If the decoder is a dual DC/DCC decoder-which most have been for awhile-then if DC is going through the tracks and inputted to the decoder then the decoder runs the motor on DC directly with no DCC CV's or other effects. Runs the same as an engine with no decoder installed..
If DCC, which is AC in the tracks then the decoder converts the AC to DC and runs the motor on DC as well as giving it what ever DCC commands have been programmed.

[skipgear]

So, a DCC loco still uses it's decoder and DCC stuff even when it's on a DC only track? 

What about DCC ready locos? Do they need more volts because of their DCC stuff, when it's on DC only track? (or does it only apply to actual, decoder installed DCC locos?)

Poliss stated what DCC ready means.
As for the DCC when using DC. (And I hope this makes sense)
If the decoder is a dual DC/DCC decoder-which most have been for awhile-then if DC is going through the tracks and inputted to the decoder then the decoder runs the motor on DC directly with no DCC CV's or other effects. Runs the same as an engine with no decoder installed..
If DCC, which is AC in the tracks then the decoder converts the AC to DC and runs the motor on DC as well as giving it what ever DCC commands have been programmed.

Actually, when on DC, the CV setting still have an effect. Momentum and lighting effects still work on DC and many decoders even have seprate CV's to determine what does and does not function when the loco is running on DC.

When on DC the decoder is still in the circuit and doing it's thing. It uses input voltage to determine the pulse width to the motor and thus the speed. When there is a decoder in a loco, it is never running on pure DC.

[poliss]

It's a little more complicated than that, depending on who made the decoder. The Loy's Toys website explains the difference between  "Automatic Analog Conversion" on decoders and "Dual Mode" decoders.
http://www.loystoys.com/info/analog-conversion.html

[skipgear]

It's a little more complicated than that, depending on who made the decoder. The Loy's Toys website explains the difference between  "Automatic Analog Conversion" on decoders and "Dual Mode" decoders.
http://www.loystoys.com/info/analog-conversion.html

Not really. I have experimented and Bachmann decoders maintain their effects on DC.

Backwards compatability with DC is an NMRA standard. All NMRA certified decoders will work on both DC or DCC in their default setting. Many decoders allow you to turn that feature off if you want. Some use it as safety when running on layouts with both DC and DCC. When the loco hits DC, it stops.

[poliss]

The Bachmann 36-558 decoder cannot be used on DC as Bit 2 of CV29 is not supported on this decoder.
Only CVs 1, 7 and 8 are mandatory according to the NMRA Recommended Practices.

[skipgear]

That decoder is for the european market and is not NMRA compliant.  The only mention of NMRA on the product sheet is when talking about 14, 28, 128 speed steps.

http://www.bachmann.co.uk/pdfs/36-558.pdf

Any decoder that is NMRA compliant will run on DC.