Will S3 Computer accept outside NMEA Heading?

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Wimpress,

According to section 1.7 of the SmartPilot Series Commissioning Guide, these autopilots may be interfaced to a 4800 BAUD NMEA 0183 source of heading data. If using a 4800 BAUD NMEA 0183 source of heading data, it is recommended that the data source be gyro stabilized and that it have an update rate of 10Hz. Slower update rates will result in more sloppy autopilot performance.

The S1/S1G/S2/S2G/S3/S3G autopilot course computers will processes their signals in this order of priority:
1. Fluxgate compass
2. NMEA compass
3. SeaTalk compass

This means that if you want to use a NMEA compass as the primary compass, you need to disconnect the fluxgate compass. Should the MFD additionally require heading data to support its heading dependent features, then the NMEA 0183 output of the heading sensor should be paralleled and connected to both the NMEA 0183 inputs of the autopilot course computer and MFD ... or to the 4800 BAUD input leads of the AIS650 should it in turn be interfaced to the MFD via 38400 BAUD NMEA 0183 communications.