Frequent No Pilot Alarms

[Chuck - Raymarine - Moderator]

Hans,

Q1. SeaTalkng converter gets power from SPX, assumption since disconnecting the SPX connection puts out green light.
The other SeaTalkng block gets power in with Black/Red (B/R) seatalk cable.
A1. It is incorrect for the SeaTalkng backbone to be powered from two points as you have suggested. It is also generally not recommended that a SPX10 Autopilot Course computer supply power to a STng backbone featuring any SeaTalkng devices other than the autopilot control head, autopilot course computer, and Data Master MFD. Should a system feature additional SeaTalkng / NMEA 2000 devices as does yours, then the SPX10 Autopilot Course Computer's SeaTalkng POWER switch should be configured to the OFF position. The spur within the SeaTalkng backbone chosen to connect the SeaTalkng Power Cable's to the should be located at the approximate midpoint of the backbone's LEN Load, whereas the spur chosen within your diagram is at one of the extreme ends of the backbone. Additionally, should switching the SPX10's SeaTalkng POWER switch OFF as you have indicated cause the ST-STng Converter's STATUS LED to cease being illuminated, then it would indicate a problem with SeaTalkng backbone cable connecting ST-STng Converter to the SeaTalkng 5-Way Connector and/or a problem with the backbone socket of the ST-STng Converter or the SeaTalkng 5-Way Connector (i.e. the ST-STng Converter should receive power via the backbone from the SeaTalkng Power Cable).

Q2. If I try to select GPS source on MFD I get error message "Data Selection not Possible" THe following deveices are preventing data source selection spx10 S/N
please see your user manual for details.
A2. In systems having products which block source selection, briefly disconnecting the blocking device from the backbone until Data Source Selection is completed may be used to work around this feature. Alternatively, the internal GPS sensor may be switched OFF as you have indicated that you have done.

Final note regarding your diagram: What is the box labeled "Yamarin box"?

Final note: While there definitely appears to be an issue with the backbone as indicated within the response to Q1, one last item to check is the SeaTalkng Termination Plugs for 120 ohms of resistance between its CANH and CANL pins.