A new concept in Model Railroad Control.

WDMI-27 Wi-Fi/DCC Locomotive Interface Module for Large Scales

WDMI-27 Wi-Fi/DCC Locomotive Interface Module for Large Scales

In stock now.


You can install this Wi-Fi/DCC Interface in many large scale locomotives together with your choice of suitable Sound or Non-Sound DCC Decoder. This module provides DCC signals to the decoder controlled by hand-held throttles supporting the Hoffman WiThrottle protocol as used by JMRI. Examples are WiThrottle on Apple IOS, Engine Driver on Android and the popular TCS UWT-100 Universal Wi-Fi Throttle. DC power can be supplied from a 12 volt battery. YOU DO NOT NEED TO INSTALL JMRI!

Read the Quick Start Document Read the Full Manual    Update your Firmware

SKU :WDMI-27 Categories : Mobile Wi-Fi/DCC Interfaces,Mobile Controllers Tag :Wifi Control

WDMI-27 Wi-Fi/DCC Locomotive Interface Module for Large Scale

This module replaces the WDMI-24 and can be installed within many large-scale model locomotives to provide Wi-Fi control of a DCC Decoder installed in the locomotive. It is compatible with NMRA compliant decoders.

An improvement over the WDMI-24 is that you can now drive the locomotive using the Engine Driver app by M. Steve Todd on Android phones or tablets, WiThrottle app by Brett Hoffman on Apple IOS iPhones or iPad and the new and popular TCS UWT-100 Universal Wi-Fi Throttle. You can also use the WifiTrax Loco Operator app. The module has also been subject to a redesign which means that it runs much cooler, has status LEDs and short protection.

The unit is intended for installation in battery powered locomotives with 10-18 Volt batteries.

Functions such as lighting and sound are all controllable from your hand-held device and custom function naming which provides labels for your chosen app or hand-held throttle Wi-Fi. In fact the capability is similar to our WFD-30 except that you only have one locomotive in which the WDMI-27 is installed. You can install these modules in as many locos as you like and each loco then appears as its own WiThrottle server.

The WDMI-27 provides Service Mode and Opertational Mode CV programming capability via Wi-Fi using a Web Page. Locomotives installed with this unit do not need to be placed on a programming track.

Read about Wi-Fi/DCC

Read the Quick Start Document

WDMI-27 Wi-Fi/DCC Locomotive Interface Module

Preliminary Specification - Subject to change until product is released for sale.


Length: 69mm (2.72") Width: 30.5mm (1.20") Maximum Height: 11.0mm (0.43")

Functions and Modes of Operation

Installs in your locomotive to provide direct Wi-Fi controlled Bipolar DCC to your choice of DCC decoder. You must select a DCC decoder appropriate to the requirements of your locomotive. This can be sound or non-sound. All DCC functions are supported. Use our Loco Operator software to drive your locomotive using direct or infrastructure Wi-Fi.

Unit provides service mode and operational mode programming using a web page user interface. Locomotive does not need to be placed on a special programming track.

Output Ratings

Maximum Continuous Current: 3.0 Amp. Maximum Stall Current: 6.0 Amp.

Power Supply Options

(1) 10 - 18 Volt Battery. Observe Polarity.


(1) Protection against short of outputs. Blue LED flashes. Auto reset when short removed.
(2) Protection against reverse battery connection.

LED Indicators

(1) Green LED flashes to show network traffic, on constant to show home net connection.
(2) Blue LED Lights to show DCC is being generated, flashes when short detected on output.


Use your own method of installation such as adhesive mounting tape.


(1) Screw terminals for battery connection. Plus and Minus. Please observe correct polarity. Reverse polarity protection provided.
(2) Screw terminals for DCC output connection to your suitable large-scale DCC Decoder.

Read the Quick Start Document