10 SmartPilot Series Commissioning GuideIsolated control unit, single power supply (S2 and S3computers only)If you have two control units, we recommend that you connect one to eachSeaTalk terminal. In the following illustration:• the SmartPilot computer provides power to the SeaTalk system• one control unit is connected on its own to SeaTalk A so it is isolated againstany possible failure of SeaTalk BIf the SeaTalk B line fails, the isolated control unit will switch to Standby mode asa safety measure. By pressing auto on the isolated control unit you can regain fullautopilot control.Note:Depending on the number of SeaTalk units and the total length of SeaTalk cabling,you may need to provide12 V power supply to each end of the SeaTalk bus (‘ring-main’style). Refer to the instrument handbook for more information.Separate SmartPilot computer and instrument powerAnother option is to provide separate power supplies to the SmartPilot computerand SeaTalk system so you can have independent, switched instrument and pilotsystems.Note:DO NOT connect the SeaTalk RED wire at the SmartPilot terminalWARNING: Use correct fuseThe fuse supplying the instrument system MUST be rated at 5A orless.The behavior of the computer and the instruments now depend on where poweris applied to the system.Course computerpower supply(via breaker/fuse)Isolated control unit, single power supplySecondcontrol unitIsolatedcontrol unitD6383-1ST60 instrumentsSeaTalk BSeaTalk ASeaTalk busExtra connection on larger SeaTalk systemsSmartPilotcomputer
