DecoderPro Comprehensive Programmer

Motor Control Pane

The Motor Control Pane includes those CVs that allow you to fine-tune the performance of the locomotive's motor for slow speed starts and smoother running.

The contents of this pane will vary significantly between different decoders. In this case, the Kick start, Acceleration rate, Deceleration rate, and Speed stabilization CVs are listed here.

Kick start is an extra burst of power at the first speed step to help start balky motors. Compare this to the "Minimum voltage" CV we'll see in the next pane, which is a sustained increased level of power. Between the two it is quite possible to tune a decent quality locomotive so that it creeps at less than a tie a minute.

Acceleration and deceleration rates help simulate a locomotive under load - but don't use them unless you have very clean track, because an interruption of power can make a locomotive stop and cycle through the acceleration curve again! High deceleration rates can make station stops and switching realistic, but very challenging!

Every manufacturer implements "Back EMF" or "Speed stabilization" differently. See your decoder documentation for the best ways to implement these variables, and be prepared to do a lot of experimenting! However they do it and whatever they call it, you should find it here.

Some suggestions on using the basic motor controls and programming on the main.

Unless you want to get into some precision speed matching, you probably won't need to use the Speed Tables you'll see on the next page - you'll be able to accomplish much of what you want using just Kick start (this page), and Start Volts, Mid Volts, and Max Volts (next page)... but how to do this?

Start with the Kick start value, and Programming on the main rather than the programming track. Set the locomotive to be programmed on throttle step 1. If it moves at all, don't change the Kick start value. If it doesn't move, slowly step up the throttle until it does. Then, turn the throttle down. If the locomotive stops at the same setting it started, you won't need to set the Kick start value. However, if it continues to run at a slower speed than it would start, then increase the Kick start value until it will start and run at its slowest possible speed.

Now, if the locomotive isn't running at throttle step 1, increase the Start Volts value without changing the throttle until the locomotive barely crawls... you can usually get this down to a speed of a tie a minute or so if you like! Since you are doing this in "ops mode" or "programming on the main", so you can make these changes while the locomotive is actually running. Don't forget to write the value changes to the decoder - they won't take effect unless you do.

Now, set the top speed of the locomotive. Run the throttle up to full, and lower the Max Volts value until the locomotive runs at the maximum speed you want it to reach, but don't forget that adding a train will slow it down!

Finally, set the Mid Volts value about half-way between Start Volts and Max Volts. Setting it above or below the median of the Start Volts and Max Volts values will give you a crude, three point speed table.

There are no hard and fast rules for the exact numbers to use. Even identical locomotives with identical decoders will need different numbers, due to variances in motors and drive trains. Experiment with the settings - DecoderPro makes it easy!

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