Garmin GHP 20 Marine Autopilot System for Steer-by-Wire Installation Instructi - Page 10

Building a Basic NMEA 2000 Network for the GHC 10 and the CCU Notice You must connect the included NMEA 2000 power cable to the boat ignition switch, or through another in-line switch. The GHC 10 will drain your battery if the NMEA 2000 power cable is connected to the battery directly. 1. Connect the three T-connectors ➊ together by their sides. ➏ ➐ ➍ + - ➌ ➎ ➊➋ ➑ ➑ 2. Connect included NMEA 2000 power cable ➋ to a 12 Vdc power source ➌ through a switch. Connect to the ignition switch ➍ of the boat if possible, or through an in-line switch (not included). 3. Connect the NMEA 2000 power cable to one of the T-connectors. 4. Connect one of the included NMEA 2000 drop cables ➎ to one of the T-connectors and to the GHC 10 ➏. 5. Connect the other included NMEA 2000 drop cable to the other T-connector and to the CCU ➐. 6. Connect the male and female terminators ➑ to each end of the combined T-connectors. Connecting Optional Devices to the GHP 20 Autopilot System To use advanced features of the GHP 20, an optional NMEA 2000-compatible or NMEA 0183-compatible GPS device can be connected to the NMEA 2000 network or to the GHC 10 through NMEA 0183. NMEA 0183 Connection Considerations • To identify the Transfer (Tx) A(+) and B(-) wires for your NMEA 0183-compatible device, consult the installation instructions for your device. • When connecting NMEA 0183 devices with two transmitting and two receiving lines, it is not necessary for the NMEA 2000 bus and the NMEA 0183 device to connect to a common ground. • When connecting a NMEA 0183 device with only one transmitting (Tx) line or with only one receiving (Rx) line, the NMEA 2000 bus and the NMEA 0183 device must be connected to a common ground. Connecting an Optional NMEA 0183-compatible Device to the GHC 10 1. Determine the NMEA 0183 connection assignments of your NMEA 0183-compatible device. 2. Connect your NMEA 0183-compatible device to the GHC 10, based on the table below. GHC 10 Data Cable Wire Color Function Blue Tx/A (+) White Tx/B (-) Brown Rx/A (+) Green Rx/B (-) Three examples of various connection situations are provided in the appendix (page 14). 3. If necessary, use 22 AWG (.33 mm2) twisted-pair wire for extended runs of wire. 4. Solder and cover all bare-wire connections. 10 GHP 20 Installation Instructions