This week I replaced my old Garmin GPSMAP® 740 with a brand new B&G Zeus™ 3S 9 chartplotter with C-MAP cartography. I’m excited about using this because I’ve used older B&G Zeus products on friends boats and this has everything I’m used to with more processor speed.
I had earlier upgraded to communication in my boat to connect the older Raymarine Seatalk instruments to the NMEA 2000 network using a Raymarine SeaTalk1 to SeaTalkng converter kit (Part Number E22158) with a blue DeviceNet adapter connecting to my NMEA 2000 backbone, and a white DeviceNet adapter connecting to my Garmin GPSMap 740. This allowed my garmin to show a few more details and my raspberry pi to capture and log the data from the depth and wind instruments.
I was hoping that beyond the physical changes to my instrument pod with the installation of the new B&G unit, the wiring changes would just require disconnecting the Garmin from the NMEA2000 connection and connecting the B&G to the same connection.
I did that. Then when I powered on the B&G, it asked for confirmation to discover all connected devices, which I had it do. It wasn’t seeing the results from the raymarine devices on the network, though it was getting AIS targets from the Garmin AIS 300 receiver and seeing my new fusion radio, both on the NMEA2000 bus. The communication path to either of those units was via the Seatalk converter, so I was confused as to if the B&G couldn’t see the old instruments, and spent a couple of days looking for possible solutions.
Most of the solutions I seemed to run across made me think that there may be too much power loss on the length of NMEA2000 backbone cable reaching from inside nav station to my outside pedestal. When I’d originally installed the converter kit, I spliced in power in the pedestal. Power was supplied directly to the converter, and it provided power to the NMEA2k backbone. During my installation of the B&G I attempted to do some wiring cleanup. I removed the power to the converter, and provided power to the NMEA2k bus in the nav station.
Here are several links to discussion that suggest power across the length of the backbone may be my problem:
I took video of the status led blinking on the converter, and it never was reporting low voltage. It was definitely reporting something with data, but I wasn’t sure if it was the first or second from the list.
I wasn’t excited about cutting and splicing my pedestal power connection again to provide power directly to the converter, and while playing around and power cycling everything, I realized that if I power cycled the converter/nmea2k bus, and brought up the B&G and just looked at the instruments, the converter was visible in the B&G!
If I selected it, I could see all the data it was publishing from the instruments on the NMEA2k bus.
That seemed like success! (The Sea Temperature reading has been whacky since I’ve bought the boat, and I can’t seem to figure out how to get it to read the correct temperature on the original ST60+ Tridata either.) So I told the B&G to auto select it’s data sources again.
After doing that, the Seatalk converter no longer was visible in the list of devices, or the data it was publishing. I also figured out that my Raspberry Pi stopped logging the data from the instruments when this happened. (I’m pretty sure my raspberry pi is the device at the top of the device list with — under both Model ID and Serial No. Fixing that is a low priority task for me. If you know how to properly configure the Pi please leave a comment pointing out what I should do. This is the platform I’m running.)
After several tests, I figured out that my Raymarine instruments continue working and putting data on the NMEA2k bus as long as I don’t have the B&G auto discover sources. I manually went through and configured the sources in the B&G settings, and was able to get things configured as I want.
I’m not 100% satisfied because I don’t think I should be able to take the converter offline with whatever commands the B&G is sending over the NMEA2k bus, but I’m happy that I didn’t have to splice more cables this week.