Seatalk 1 adding a Vyacht wifi multiplexer, needs advice.

[Chiliblue]

Hi,

I am planning to add a Vyacht net 'wifi nmea/seatalk multiplexer' and an ais receiver to my boats set up.

The ais targets won't show up on my old raymarine plotter/radar but that's ok, I always have my tablet on me I I use that for passage planning and just transfer the waypoints to the plotter unit. I would however really like to have the instrument information sent out via wifi.

My system is pretty simple, gps is fed to the seatalk using the ST60 multi nmea input, power is brought in to the ST60 multi via one of the seatalk ports, the other instruments are daisy chained off the other Seatalk port on the st60 multi > st60+ tridata > st60+ wind > plotter/radar.

The plotter only has on single seatalk port.

Ideally I would like to interface the Vyacht unit with seatalk rather than nmea, because although the st60 multi adds in the nmea data to seatalk I am not sure if it outputs the compatible seatalk sentances to the nmea out on the unit.

Does anyone have any thoughts on how I can do this with the equipment at hand? Would wiring the data and gnd to the Vyacht from the seatalk port that is also bringing in the power work? Or am I wrong about the span of data the st60 multi will output on nmea?

Thanks in advance.

 

[prv]

The nice thing about good old Seatalk is that it's a common bus, everything on it is just connected in parallel to the one data wire and the topology doesn't really matter. So yes, anywhere you can make a connection to that magic yellow wire should be fine, including (if necessary) cutting it and adding a junction box.

Pete

 

[Chiliblue]

So yes, anywhere you can make a connection to that magic yellow wire should be fine, including (if necessary) cutting it and adding a junction box.

Pete

Thanks for the response Pete,

Can I just clarify that, are you saying I could just create a spur of the seatalk cable running between the multi and the next instrument. The Vyacht only has inputs for the data and gnd as it, like the plotter, is independently powered.

I do still need to connect the seatalk gnd to the Vyacht? Or do I only have to connect the data wire? The plotters connection is just data and gnd so I suspect the gnd is needed.

Thanks

 

[prv]

Can I just clarify that, are you saying I could just create a spur of the seatalk cable running between the multi and the next instrument. The Vyacht only has inputs for the data and gnd as it, like the plotter, is independently powered.

I do still need to connect the seatalk gnd to the Vyacht? Or do I only have to connect the data wire? The plotters connection is just data and gnd so I suspect the gnd is needed.

Correct on both counts. It's quite possible that it would work without the connection to Seatalk ground, on the assumption that all the power supply negatives are at the same potential, but it would be better to explicitly make that connection.

Pete

 

[Bernd]

Yes, for Seatalk basically any topology works: daisy chain, star, bus - as long as you don't run too many devices on too many meters. To connect our router you can just use a second pair of wires (spur) to the plotter or any other instrument. Raymarine instruments have their two ports connected to each other internally as well. You should use the ground-in of our router's Seatalk though as its an isolated interface. Particularly on last year's model where ground is 100% isolated and signal current just can't flow.

We usually advise to use a separate power cable from the battery or panel as Seatalk power often has glitches - no issue for a wind instrument but a microcomputer which might reboot - causing some delay when restarting.

The ST60 Multi will translate quite a few navigational sentences from NMEA to Seatalk - but no wind, depth or water-tri-data.

Bernd/vyacht

 

[ianj99]

On the Shipmodul multiplexers, input 4 is Seatalk compatible, BUT you connect red to the + input and yellow to the -ve. No ground needed. (The input is the usual opto isolator but presumably it needs this connection method to get the correct polarity of signal.)

 

[Chiliblue]

On the Vyacht net it is a isolated input, so I think the grid is needed, it is only has a connection for data and gnd... Like the plotter no 12v+ required. So Inthink you are right it needs the gnd as a reference for the data wire. I'll ask the Vyacht designer.

 

[Chiliblue]

Sorry I missed your response before Bernd, thanks for the clarification.

In my install it makes sense to spur off the st60 multi which is the first in my seatalk chain and where power is introduced. My concern is whether I could connect to the power side where the gnd and 12v+ is ( that would be the boats gnd) or to splice in on the side between the st60 multi and the next seatalk instrument.

It depends on how I wired things as I used short seatalk patch cables and extended them as needed. My hope is I used spade connectors and left the moulded ends at the other end. I am waiting for the delivery of a ais antenna before I install.

Regardless I will take the data and seatalk gnd to the Vyacht and will run power to it directly.