Trim Adjust

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Decoder Features

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

Forward/Reverse Trim

Vstart
Vmid
Vhigh

Programming
Addressing
Decoder 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

Trim Adjust is the feature incorporated into the multifunction decoder by CVs 66 and 95.

These Configuration Variables are Optional, so your decoder may not include them.

Why the Need for Trim Adjust

Due to tolerances in the gear trains and bearings, a vehicle may not operate at the same speed in both directions with the same throttle setting. Trim Adjust allows user adjustments to the voltage supplied to the motor in forward or reverse rotation. This allows the motor (and vehicle) speed to be altered in either direction to make them match.

Forward Trim

Forward Trim specifies a scaling factor to be applied to the calculation of the motor drive voltage when the locomotive is operated in forward. It is interpreted as n/128. Setting CV 66 to Zero disables the feature.

Reverse Trim

Reverse Trim specifies a scaling factor to be applied to the calculation of the motor drive voltage when the locomotive is operated in reverse. It is interpreted as n/128. Setting CV 95 to Zero disables the feature.