Overview

The Simrad 000-13336-001 is a NAC-3 autopilot core pack that combines the NAC-3 autopilot computer, Precision-9 compass, RF25N rudder reference sensor, and a Micro-C NMEA 2000 backbone starter kit. It is intended for rudder-steered boats above 10 metres (35 feet), and the NAC-3 drive output can run 12/24 V reversible motors up to 30 A continuous (50 A peak for 1 second).

This pack covers the core sensors and network pieces for a below-deck autopilot install, but you still need to add a drive unit that matches your steering system and a control interface (a dedicated autopilot controller or a compatible Simrad multifunction display). The system uses NMEA 2000 for data sharing across the boat and also supports NMEA 0183 input when you need to bring in legacy data.

With the Precision-9 providing heading and rate-of-turn data and the RF25N supplying rudder position feedback, you get the information the autopilot computer needs to steer cleanly in real conditions, from dockside slow-speed handling to longer runs offshore.

Key features

• Core pack for rudder-steered boats above 10 metres (35 feet); add a drive unit and a control interface to complete the system
• High-current NAC-3 drive output for 12/24 V reversible motors: 30 A continuous with 50 A peak (1 second)
• Supports hydraulic pumps, mechanical drives, hydraulic linear drives, and solenoid valves when matched to the steering system
• NMEA 2000 Micro-C networking for heading sensor, rudder feedback, autopilot controller, and compatible multifunction displays
• NMEA 0183 input for integrating selected legacy instruments and data sources
• Precision-9 solid-state compass with IPX7 rating and heading accuracy of +/-2 degrees after calibration; outputs heading, rate of turn, pitch, and roll over NMEA 2000
• RF25N rudder reference sensor with NMEA 2000 Micro-C interface and IPX6 rating for installations in exposed machinery spaces

Compatibility and fit

This core pack is aimed at larger sail and power boats with a conventional rudder and steering gear where a physical rudder feedback sensor is part of the plan. It is suitable for use with high-current drive pumps such as Simrad RPU160 and RPU300, mechanical drives such as the Simrad DD15, hydraulic linear drives such as the HLD2000 series, and solenoid valves.

It is a solid fit for coastal cruisers, offshore-capable boats, sportfishers, and commercial-style setups that want autopilot steering tied to both a rate compass and direct rudder position feedback. The drive unit choice should be based on your steering type and current draw, since the NAC-3 is built to handle higher-current loads.

Installation and setup

The included Micro-C backbone hardware can be used to build a small NMEA 2000 network from scratch or to tie this autopilot into an existing backbone. Precision-9 and RF25N connect via Micro-C, and the NAC-3 uses the network to share sensor data with your autopilot controller and display.

Mount the Precision-9 where it can stay clear of magnetic interference; it can be bracket mounted on a bulkhead or flat surface, and its IPX7 rating supports external mounting locations when needed. Install the RF25N so the linkage moves smoothly through full rudder travel; it can be mounted horizontally, vertically, or upside-down.

Auto-tuning and automatic compass calibration handle much of the setup once wiring is complete. The drive wiring is high-current, so cable sizing and circuit protection should be matched to the requirements of your specific pump or drive unit.

What’s included

• NAC-3 autopilot computer
• Precision-9 solid-state compass
• RF25N rudder reference sensor with transmission link and 5 m NMEA 2000 Micro-C cable
• Micro-C backbone kit with network power cable, 4.5 m NMEA 2000 cable, three T-connectors, and two network terminators