[CA] Seatalk to Garmin 740s?

[duetto]

hi all,

we have a bidata on our flybridge which is connected to seatalk. we also have a standalone garmin 740s. the bidata is having problems and i'd like to interface the 740s to the seatalk network to get depth data.

has anyone done this? if not, can anyone point me to a solution?

thanks in advance,

john (duetto)

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum John,

While the Garmin 740s appears to not have a NMEA 2000 communications interface, it appears to have a NMEA 0183 communications interface, permitting data to be transmitted to other devices. It is recommended that the depth transducer be disconnected from the ST40 Bidata's transducer terminals. The SeaTalk bus may then be disconnected from its present source of power and then interfaced to the SeaTalk socket of a SeaTalk to SeaTalkng Converter Kit. A NMEA 0183 to SeaTalkng / NMEA 2000 data bridging device (ex. Actisense NGW-1-ISO-STNG, etc.) may then be used to interface the NMEA 0183 output port of the Garmin 740s as a spur the SeaTalk to SeaTalkng Converter. Please click here to view a FAQ addressing interfacing SeaTalk devices to a SeaTalk to SeaTalkng Converter.

[skipmac]

Have a similar questions. I have an ST40 Bidata with depth/temp and speed transducers connected. Also have a Garmin 740s that is connected to a Simrad AP via NMEA2000 micro-c network (yes, my 740s is NMEA2000 capable). Where the ST40 is mounted is not completely waterproof so I want to move it to a dry spot (that I can't see from the helm) and put the depth and speed data on the NMEA2000 network.

I think this should be simple but have been unable to view or download the manuals from the Raymarine website to confirm the details so hope you can help.

This is what I think.

1. Connect the ST40 bidata to the Seatalk-Seatalkng converter (part number E22158). From photos it appears that converter comes with a cable that plugs directly into the 3-pin Seatalk port on the back of the ST40 bidata display? The transducers will stay connected to the ST40 display as before.

2. Connect the ST-STng converter to a T on my NMEA backbone which I think will take an adapter cable? Which cable and part number?

3. Is that all or will I need any additional cable, converter, adapter or black box?

The converter has 5 ports and includes two cables (power and ST) and two plugs, two terminators. Do all the ports have to be filled with cables, plugs or terminators? Assume the manual will cover this?

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum skipmac,

Contrary to your statement, the ST40 Instruments were indeed designed to be installed and operated in direct exposure to the marine environment. These instruments were designed to be waterproof to the IPX5 Standard. Should an ST40 Instrument have experienced a water intrusion failure and should one be seeking to install it in a location which will be exposed to weather, then it would be recommended that the instrument be serviced by Raymarine’s Product Repair Center or replaced with an i40 Instrument.

Q1. From photos it appears that converter comes with a cable that plugs directly into the 3-pin Seatalk port on the back of the ST40 bidata display? The transducers will stay connected to the ST40 display as before.
A1. Correct. The supplied SeaTalk to SeaTalkng Cable will be used to interface the SeaTalk socket (yellow) of the SeaTalk to SeaTalkng Converter to the SeaTalk socket of the instrument or a D244 Junction Block within the vessel's SeaTalk bus.

Q2. Connect the ST-STng converter to a T on my NMEA backbone which I think will take an adapter cable? Which cable and part number?
A2. The ST-STng Converter is designed to be installed a NMEA 2000 backbone component, not as a spur component. Accordingly, the ST-STng Converter will be interfaced to the currently installed SeaTalkng backbone via one of the following methods:
- at the end of the backbone: SeaTalkng Blanking Plugs (black) will be installed within the ST-STng Converter's two spur sockets (white). A SeaTalkng Termination Plug (blue) will be installed with one of the backbone sockets (blue) of the ST-STng Converter. The NMEA 2000 Terminator will be removed from the end node of the existing NMEA 2000 backbone to which the ST-STng Converter will be interfaced. An appropriate length SeaTalkng Backbone Cable will be connected to between one of the ST-STng Converter's backbone sockets (blue) and a backbone socket within the currently installed NMEA 2000 backbone. Please click here to view a FAQ addressing how the SeaTalkng backbone cable may be modified/adapted to be mated to the backbone socket of a NMEA 2000 backbone which has been constructed from third party NMEA 2000 networking components.
- within the middle of the backbone: SeaTalkng Blanking Plugs (black) will be installed within the ST-STng Converter's two spur sockets (white). A SeaTalkng Termination Plug (blue) will be installed with one of the backbone sockets (blue) of the ST-STng Converter. An appropriate length SeaTalkng Backbone Cable will be connected to between each of the ST-STng Converter's backbone sockets (blue) and a backbone socket within the currently installed NMEA 2000 backbone. Please click here to view a FAQ addressing how the SeaTalkng backbone cable may be modified/adapted to be mated to the backbone socket of a NMEA 2000 backbone which has been constructed from third party NMEA 2000 networking components.

Q3. Is that all or will I need any additional cable, converter, adapter or black box?
A3. See the response to Q2.

Q4. The converter has 5 ports and includes two cables (power and ST) and two plugs, two terminators. Do all the ports have to be filled with cables, plugs or terminators? Assume the manual will cover this?
A4. See the response to Q2. Should the currently installed NMEA 2000 backbone be powered, then the supplied SeaTalkng Power Cable will not be used, as the ST-STng Converter will instead receive power from the currently installed backbone when installed as specified within the response to Q2.

[skipmac]

HI Chuck,

Thanks for the detailed reply. Since this is my first venture into networking marine instruments I will read through it a couple of times to make sure I get the details correct. Hopefully I can digest this without having to ask further questions.

Regarding the ST40, glad to hear the display is waterproof. However the problem I observed is not the instrument but where the cables plug into the back. The location is inside a console in the cockpit out of direct weather but during hurricane Matthew the winds blew a lot of spray under the console and wet the back of the ST40 bidata. When I later removed the teak trim around the display for revarnishing I found green corrosion around the end of the Seatalk plug where it had gotten soaked. I would like to remount it in the same location but it will get wet again under the right (or wrong) conditions.

I did caulk a yogurt cup around the mounting [censored] leaving just a small [censored] for the cables but that wasn't enough. Would you recommend using some kind of caulk or sealant over the wires where they plug into the bidata? Maybe butyl tape or ???

Regards
Skip

[Chuck - Raymarine - Moderator]

Skip,

Please click here to view a FAQ addressing this subject. You may want to consider use of the dielectric compound referenced within the FAQ on your ST40 instrument's SeaTalk and transducer pins.

[skipmac]

Hi Chuck,

Have all the bits and getting ready to put this together but have a couple of small points I would like to confirm.

Q1. I will connect the Seatalk-Seatalkng converter (blue connection) to the end of an existing NMEA2000 backbone (replacing the terminator). Your previous answer said to use a Seatalkng backbone cable with an adapter for this connection. The Seatalk-Seatalkng converter came with a 1 meter cable labeled as a spur cable but it looks the same as a short backbone cable. Can I use that spur cable (with adapter of course) for connecting the converter to the NMEA backbone?

Q2. The existing NMEA2000 backbone does have power which as you explained will power the ST-STng converter. I assume then the ST40 Bidata will receive its power from the converter since it is powered by the backbone.

Thanks again.

[Chuck - Raymarine - Moderator]

Skip,

Q1. I will connect the Seatalk-Seatalkng converter (blue connection) to the end of an existing NMEA2000 backbone (replacing the terminator). Your previous answer said to use a Seatalkng backbone cable with an adapter for this connection. The Seatalk-Seatalkng converter came with a 1 meter cable labeled as a spur cable but it looks the same as a short backbone cable. Can I use that spur cable (with adapter of course) for connecting the converter to the NMEA backbone?
A1. Negative. SeaTalkng Spur Cables (white w/black stripe) cannot be mated to a SeaTalkng backbone socket (blue). You will need to obtain an appropriate length of SeaTalkng Backbone Cable for the stated purpose.

Q2. The existing NMEA2000 backbone does have power which as you explained will power the ST-STng converter. I assume then the ST40 Bidata will receive its power from the converter since it is powered by the backbone.
A2. Correct.

[skipmac]

Hi Chuck,

Again thanks for the great support. Regarding Q1, I looked more closely at the converter and cables this weekend and realized that yes, the spur and backbone cables are not the same. I think I was looking at the spur and the power cable which do appear to be the same.

Will try to work on the installation this week. With any luck you won't hear from me again except to report success.


Regards
Skip

[Chuck - Raymarine - Moderator]

You're welcome.