NAC-2 versus NAC-3 is primarily a drive-control selection. The computers serve different current requirements; they are not simply basic and premium displays. Choose the actuator or pump suitable for the boat, then establish which supported computer can operate it.
Side by side
B&G NAC-2 vs B&G NAC-3: specifications and installation
| Criterion | B&G NAC-2 | B&G NAC-3 |
|---|---|---|
| Manufacturer positioning | Low-current drive applications | High-current drive applications |
| Published output | 8 A continuous / 12 A peak | 30 A continuous / 50 A peak |
| Display decision | Specify supported control and display separately | Specify supported control and display separately |
| Selection evidence | Drive, clutch and feedback requirements | Drive, clutch and feedback requirements |
Specifications and installation scope from manufacturer documentation. Any AUD prices shown are indicative; confirm current package contents and installed costs with a dealer.
Which should you choose?
Choose if
Which autopilot configuration suits your boat?
Choose B&G NAC-2 if…
- The assessed drive and complete installation are supported by NAC-2.
Choose B&G NAC-3 if…
- The assessed drive requires a supported high-current NAC-3 installation.
Keep computer output separate from battery consumption
The output rating describes what the computer is designed to operate. It is not a prediction of the average current the boat will consume while steering. Build the power budget from the actual drive and expected use, and have supply protection and cabling specified for the installation.
Check the surrounding system during a retrofit
Record the existing drive, clutch, rudder feedback, heading sensor and controls. Ask the supplier to identify the supported retained parts and any required replacements. If the computer is changing because the drive is changing, include mechanical work and recommissioning in the same project rather than pricing the computer in isolation.
Questions
B&G NAC-2 vs B&G NAC-3: frequently asked questions
Will NAC-3 make the same drive stronger?
The computer does not change the actuator’s mechanical rating. Select and assess the complete drive installation.
Are the current ratings an energy-use estimate?
No. They are output capability figures, not average operating consumption.
Can the existing Triton2 controls remain?
Confirm the exact controls, software and supported configuration with the supplier before assuming reuse.
Manufacturer sources for this comparison
Source-based comparison checked 2 October 2026. No comparative sea trial is claimed.
Autopilot training after installation
The best pack badly understood is a worse autopilot than a modest one used well. A half-day handover covers modes, override, alarms and a failure drill.