Speed Tables

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Yes I am new to DCC and this site. I was wondering if there is anywhere I could go to find speed table standards for my locomotives. By that, I know all of the locomotives will grealty surpass thier scale speeds. IE - What is the top speed of an E8 in scale inches per second (feet/per second)? I figured with all of the other things I have come across maybe this is out there somewhere too. I have dozens of engines that I need to start configuring. Thanks for all of the help.


David C. Eaton

-- David Eaton (dcesharkman@yahoo.com), December 31, 2004


Hi David

The way the motor responds when we turn the throttle knob or buttons is determined by the values of the CVs in the decoder. This is done by entering values for CVs 2, 5 and 6 or CVs 67 to 94. Not all decoders support these methods.

The purpose of using this method is to change the decoder's default table so as we can make loco move as soon as we operate the throttle, slow down top speed and vary the speed change between speed steps, (smaller or larger), to make a curve instead of a straight line and to mke the curve or straight line flatter or steeper depending on personal choice and for the particular loco (switcher or passenger express).

As for actual scale speed for each of your locos, I don't know where you get that information from. Others may help here.


-- Marcus Ammann (mammann@optusnet.com.au), January 02, 2005.

Miles per hour X 17.6 = inches per second. Divide this by your scale (87.1 for HO) to yield in/sec at that scale speed on your layout. [1 mph X 17.6/87.1 = 0.202 inches per sec HO speed] For easier control of locos on your layout pick a realistic top speed like 75-85 mph for passenger locos (as opposed to what the prototype loco could actually do at the top end). [85 mph X 0.202 = 17.2 in/sec for HO] Freight locos may want to be limited to 50 smph. It's your railroad. You make the choices. If you plan on consisting locos together, they should run at the same actual speed at the same maximum speed step throttle setting.

This is a hunt & peck process given all the possible combinations of locomotive motors, gearing, decoder brand and set-up.


-- Don Vollrath (dvollrath@magnetek.com), January 03, 2005.

Hello David, A good dissertation on this subject can be downloaded from the www.cvpusa.com website. Their instruction manual for EasyDCC covers this information. One standard feature of their system is a macro to download the “canned speed tables” included. One caveat is making sure the decoders being downloaded to are NMRA DCC compliant. Some, like Digitrax, are not compliant (only compatible), and will not work. Look for the NMRA warrant if you aren’t sure. I installed 34 of these decoders before I discovered this fact. I look for the warrant on decoders before I buy them now. Regards, Jon McFadden

-- Jon McFadden (n6vc@yahoo.com), January 04, 2005.

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