Three Step Speed Table

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The Three Step Speed Table uses the Start, Mid and Maximum voltages to create a simple speed table to customize locomotive performance.

Decoder Features

Movement & speed
Back EMF
Decoder-Assisted Consisting
Dither
High Frequency
Kick Start
Loco Momentum
Loco Trim
Loco Momentum
MU consisting
Speed Steps
Speed Table
Switching Speed
Three Step Speed Table

Forward/Reverse Trim

Vstart
Vmid
Vhigh

Programming
Addressing
CV Reset
Programming
Programming Lock
User Identifier

Lighting & Effects
Directional Lights
Func Remap
FX Lighting
Master Switch

Misc
Short-Circuit
Thermal Protection
Transponding

DCC Core components

Intro
Booster
Command station
Decoder
Power supply
Throttle

Track work components

Track wiring
Track work

Three Step Speed Table

CVs Used

The following three CVs are used to create the speed table:

  1. CV2, VStart: Used to set the speed for Speed Step 1 by adjusting for the motor and drivetrain
  2. CV5, VHigh sets the maximum speed
  3. CV6, VMid adjusts the mid point speed

By adjusting their values, a response curve can be created to simulate the operation of a switcher, road switcher, or a road locomotive. Use care, as incorrect relationships between the CVs can have unpredictable results. For example, VMid must be at a value larger than that used for VStart.

Switchers do not need to go fast, slower operation is preferable. Road switchers have to function as both road locomotives and switchers, so while slow speed operation is needed, higher speeds are needed for over the road operations. Road locomotives need their speed curves set for higher speed operations, as they don't perform switching operations. So adjusting the VMid may allow for more realistic operations where reduced throttle response is needed towards the operational speed range, but more response to get the train moving.

For more details see Speed Steps.