[TG] [TG11] Network Feature Request NMEA

[Tom - Raymarine - Moderator]

Hello Finatic,

Engines don't transmit tank information - an engine would have no way to know the tank level, that needs to come from an external tank level sensor. Engines transmit fuel flow rate (litres/hour) in NMEA2000 PGN 127489, Engine Parameters Dynamic. The NMEA2000 specification for PGN 127489 says that:

Quote:0 = Single Engine or Dual Engine Port
1 = Dual Engine StarBoard
(for Multiple Engines, Instances will start from Bow, Port (0) to Stern, Starboard (n) )
n = Instance n, where n < 253

The specification for instancing of tanks (PGN 127505 Fluid Level) is more relaxed, at least in the version of the NMEA2000 spec. that I have, but it is still customary to start from zero and count up from there. That is what our software expects: if arbitrary instance numbers are used, it becomes much harder to say which is port and which starboard.

We do get requests occasionally to do arbitrary mapping/reassignment of instance numbers to tank 'names' (port, starboard etc.), but we have not yet chosen to implement this partly because any NMEA2000 transmitting device should come with a tool or method to configure those sorts of installation-level fields, and partly because of the high burden of technical support that's likely to result from the sort of random button-pushing that causes tech support calls on other matters every day.

These instances should be set to 0 and 1 through the sensor manufacturer's setup tool.

Regards,
Tom