single speed running

[TonyCoats]

I have four new Bachmann locos, DCC ready that when run on my old (like I am) DC12v analog layout,run but only at one speed! 
On or off, go at one speed or stop dead! In otherwords no acceleration or deceleration. Turning the dial is effectively the same as an on/ off switch. 
What do I need to do to make them controlable. Is this because dc is switched off on their decoder? I have been advised that I would need a dcc controller and change certain values on one specific loco, which is a Soutern E4 0-6-2 tank engine. Would this advice apply to the others? 
I would much Appreciate any advice from any members familiar with this problem.
Tony

[jjdamnit]

Hello All,

to the forums.

Your fist few post will be reviewed by the moderators so there will be a delay in seeing them.

TonyCoats

I have four new Bachmann locos, DCC ready...

The term "DCC Ready" means that there is a plug socket on the factory-installed Original Equipment Manufactured (OEM) printed circuit board (PCB) with a dummy plug. 

To install a DCC decoder this plug is removed and a compatible wiring harness or decoder is installed.

"DCC Ready" does not mean there is a decoder installed.

What output are you using on the back of your cab (controller)?

Most DC cabs have several outputs: Track Power, DC Accessory, and/or AC Accessory.

If your track is connected to the DC Accessory terminals it will provide a constant voltage and no speed control.

However, if your track is connected to the correct outputs on the cab the unit could be faulty.

Using a digital multimeter (inexpensive meters can be found for approximately $20.00 at hardware or home improvement centers) check that when the cab is at zero there is no DC voltage between the terminals. (Aligator clips can help hold the probes from the meter to the terminals.)

When you advance the throttle you should see the DC voltage increase to a maximum value of between 12- to 16-VDC.

If the voltage does not vary then the cab is probably damaged.

DC cabs are relatively inexpensive and can be found on auction sites.

Hope this helps.

Post Script: If your cab is faulty message me at the email listed on my profile and I might have a solution for you. HTH, JJDI.

[mvlandsw]

How old is your DC power pack or cab? If it is old enough to use a rheostat instead of transistors to regulate the speed it may not be able to control the output voltage to a low enough value to run more modern motors at low speeds.

Mark

[wjstix]

If you still have the boxes or paperwork that came with the engines, I would double check them. Bachmann (as JJD points out) uses the standard "DCC Ready" label to indicate there is a receptacle you can use to plug-in a decoder. However, Bachmann also labels some engines "DCC Onboard" meaning a non-sound decoder is factory installed. 

Note that apparently some older Bachmann engines were labelled "DCC Ready" but didn't have the receptacle. 20 years ago, sometimes "DCC Ready" just meant "the motor is isolated from the frame, and there may be enough room in the tender to squeeze in a decoder". So it could depend if your engines are brand new or "new old stock" that was actually made a while back.

[betamax]

Unfortunately DCC Ready is a generic term, which can mean a number of different things. Most locomotives today will have some sort of connector to allow easy installation of a decoder, but that is not always true.

[riogrande5761]

I'm curious.  What else does DCC Ready mean besides having a DCC plug built on to the mother board.

[wjstix]

riogrande5761

I'm curious.  What else does DCC Ready mean besides having a DCC plug built on to the mother board.

 

 

There is no set definition, each manufacturer used/uses their own version.

 

Long ago, model railroad engines had the plus or minus connection made directly to the metal frame. In DCC, the motor needs to be entirely isolated, so some manufacturers who's models had isolated motors said they were "DCC Ready".

 

By the 1990s, diesel models usually had a green 'light board' which was used to connect track power to the motor and lights, with diodes to create directional lighting. Manufacturers eventually began adding receptacles to the lightboard for a decoder. These too were then called "DCC Ready".