Bachmann 83054 too fast

[Rheingold]

Hi,

I'm new to this forum. I'm Stefan from Germany. Most of my trains are German but I also run some American. One of those is the Amtrak Acela #650 (Bachmann 83054) with built-in decoder. The problem is that it runs far too fast (~ 300 mph). When I run it it's already 100 mph fast with only step 9 of 128 steps (DCC)!

I can't change the maximum speed. The decoder doesn't react on programming cv 5 nor to the cv's 67 to 94.

Is there any way to make it slower?

Regards,
Stefan

[skipgear]

What is your track voltage of your DCC system? 12V is standard for N scale.

[Rheingold]

It's 20V (I can't change this. Anyhow this is the voltage that reaches the decoder not the motor. The motor voltage is controlled by the decoder and does not depend on the track voltage). I know that it's more than recommended but modern decoders can use voltages up to 22 or 24V. This is the only train that behaves like this. All other of my 50 locos (even American) don't have this problem and run normally. Also I can set the max speed to all of my 50 locos by programming cv 5 but this one here. I would consider to change the decoder but as it is built-in I can't.

[seadowns]

Hello!

Since the Bachmann on-board decoder does not support CV5 or a speed table your only chance to slow down the loco speed is in reducing the system power. I run my system with just 15V DC input which brings about 13,4V digital juice on track. This is absolutely enough for N-scale but the engines run much faster if I switch to more input, lets say 18V DC.
Here's the Bachmann decoder manual to check up:
http://www.bachmanntrains.com/home-usa/ez_content/1_Amp_Decoder_Instr.pdf

If you need furthermore information don't hesitate to contact me in german.

Regards
Mathi