[CA] [CA11] New installation multiple power inputs

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum pfrank,

Q1) Is there a reason why my dealer/installer would provide multiple power inputs as described?
A1) Some third party NMEA 2000 networking components utilize power conductors of insufficient wire gauge. Should such networking components be used within the system's powered and properly terminated SeaTalkng / NMEA 2000 backbone, then a second power insertion spur connected to the same circuit supplying the first may be installed.

Q2) What harm occurs from having multiple power inputs as described?
A2) A ground loop could be created. Ground loops may result in intermittent, erroneous, or no communications between devices which have been interfaced to the SeaTalkng network. As you have suggested, a single power insertion spur, located at the approximate midpoint of the backbone's LEN load, should be installed within the backbone. It is recommended that the power insertion to the ST60 instruments and second SeaTalkng / NMEA 2000 Power insertion be removed.

Q3) The power input to the NMEA 2000 backbone is an open circuit when the fuse is pulled. Should I pull that power cable off of its backbone connector and replace with a NMEA 2000 terminator?
A3) Negative. Termination plugs should only be installed within a backbone's two unoccupied backbone sockets (one at each end). Unoccupied SeaTalkng spur sockets should be filled with SeaTalkng blanking plugs to protect the socket.