Building an NMEA2000 Backbone

How to build an NMEA2000 backbone so the Accutroll NMEA2000 WiFi Gateway can share speed data with your TCM.

Table of contents

  1. Video
  2. Why you need a backbone
  3. Backbone components
  4. Power the backbone
  5. Starter kit
  6. Gateway placement
  7. Next Steps
    1. Need Help?

Video

Watch on YouTube

Why you need a backbone

NMEA2000 is a standardized marine network so mixed-brand electronics (Garmin, Lowrance, Simrad) share data.

Accutroll cruise control needs that bus. The gateway plugs into the backbone, listens for speed packets, and broadcasts them wirelessly to the TCM. If the boat has no backbone, build one before you expect cruise to work.

Then continue with the NMEA2000 WiFi Gateway Installation Guide.

Backbone components

A working backbone is made of:

  • T-connectors — each device joins the bus through a T
  • Two terminating resistors — one on each extreme end of the backbone
  • Drop cables — from a T to plotters, sensors, autopilots, and the Accutroll gateway
  • Power drop — a heavier-gauge drop that powers the backbone

Power the backbone

Power the backbone in one spot.

  1. Connect the power drop at the boat’s fuse or breaker panel.
  2. Fuse it 3–5 A, usually about 5 A.
  3. On the power drop, use red and black only. Snip off the blue and white communications conductors. Those wires are not used for power.

The NMEA2000 Starter Kit Bundle does not include the fuse. Add an appropriate fuse at the panel.

Starter kit

Accutroll sells an NMEA2000 Starter Kit Bundle on accutroll.com. The bundle includes:

  • Two T-connectors
  • One power drop
  • A pair of terminating resistors
  • One drop cable

Use it as a minimal cruise backbone:

  1. Put terminating resistors on both extreme ends.
  2. Use one T for the Accutroll gateway.
  3. Leave one open T for the MFD.
  4. Run the drop cable from the backbone to the MFD so GPS speed is on the bus.

Gateway placement

The gateway pigtail is fairly short. Plug the gateway into a T on the backbone.

If that location would bury the gateway behind electronics or heavy metal, buy another drop cable as an extension and mount the gateway where it has a clearer line of sight. The gateway uses 2.4GHz WiFi to reach the TCM.

Do not screw the gateway down until you have scanned its QR code. See the Installation Guide.

Next Steps

Need Help?

Copyright © 2025-2026 Innotech Marine