Another gremlin (bug) with B&G Touch CP, SH GX2200, and Raymarine i60 speed display

[Captain Larry-DH]

Decided to start another thread so as not to hijack @Rick D's, although much of my equipment is the same as his: However, my problem is that SOG (GPS) does not display on Raymarine instrument display unless the AIS is not connected:

• SOG from B&G displays on Raymarine i60 speed instrument display head with GX2200 radio turned off (AIS disconnected)
• AIS displays properly on B&G with GX2200 turned on
• SOG on Raymarine speed display turns to dashes when GX2200 is turned on (unless NMEA0813-out is disconnected from GX2200)

SOG on B&G display is not affected by this gremlin (GX2200 on or off) because it comes from its internal GPS. So this is a minor inconvenience - I still get SOG displayed on the B&G CP with AIS overlay. Display of "boat speed" (through water) on the Raymarine is not affected.

Connections: Standard Horizon GX2200 AIS-receive connects to B&G Touch 7 CP via NMEA0183. Raymarine connects to B&G CP via SeatalkNG/NMEA2000 gateway to NMEA2000-to-SIMNET conversion cable.

I called Raymarine and B&G Support separately last summer and they weren't helpful. I was expecting that, once they learned it is a mixed system, but I was hoping for some insight (particularly from B&G) because my theory is that the SOG data packets from the AIS data stream are being relayed and mixing with the SOG data packets coming from the B&G CP, and both are causing confusion in the Raymarine display (like two people talking at once). I was hoping they could help me find a setting that would turn off the relay of the AIS data packets so they wouldn't reach the Raymarine.

Anyone have any tips or insights about this?

 

[Davidasailor26]

I’d start by looking in the B&G CP at the network statistics. It should show the NMEA2000 bus status and load. Check to see if the bus status or error counts change when you turn on the AIS. Also check to see if the load increases when you turn AIS on, which would at least confirm your suspicion that AIS data is being forwarded.

There are NMEA 2000 to wifi gateways, and many MFD’s have that capability built in. If you find someone around with one that could lend it to you for a couple hours you could look at the NMEA 0183 versions of the sentences on the NMEA 2000 network. That might give you some clues as to whether the sentences change, stop, or get malformed once the AIS starts.

Also, you said the display goes to dashes when the AIS is turned on... Do you mean as soon as it has power or is there a delay, like the amount of time it takes to start getting AIS beacons? If it goes to dashes immediately I’d suspect some kind of errors at the hardware / electrical level rather than the network protocol later. Maybe some kind of power sag or weird ground loop?

 

[Captain Larry-DH]

Do you mean as soon as it has power or is there a delay, like the amount of time it takes to start getting AIS beacons?

I’d have to check that again next time I go to the boat. Thanks for your thoughts on this.

 

[dlochner]

I called Raymarine and B&G Support separately last summer and they weren't helpful. I was expecting that, once they learned it is a mixed system, but I was hoping for some insight (particularly from B&G) because my theory is that the SOG data packets from the AIS data stream are being relayed and mixing with the SOG data packets coming from the B&G CP, and both are causing confusion in the Raymarine display (like two people talking at once). I was hoping they could help me find a setting that would turn off the relay of the AIS data packets so they wouldn't reach the Raymarine.

I'm not surprised about the lack of tech support from either company. This is why it is sometimes better to stay within the same ecology.

You're probably correct about the data packets. You might try contacting SH tech support to see if it is possible to turn off the SOG packets from the VHF.

 

[mermike]

Does your GPS output 0183? What if you turn the GPS in the 2200 off and set it to your external GPS.

 

[dave_and_dd]

I think mermike is correct. Turn off the gps in the radio. The radio will get the position from the chart plotter.

Dave

 

[Captain Larry-DH]

I think you might have hit on the solution.

What if you turn the GPS in the 2200 off and set it to your external GPS.

I didn't think that's possible until your post prompted me to check the manual. I can try that, but I think it will wait until warmer weather because my present NMEA 0183 connection between the CP and the GX2200 is using only 2 wires, and I will need to make it bidirectional by adding more connected leads.

 

[mermike]

I didn't think that's possible until your post prompted me to check the manual. I can try that, but I think it will wait until warmer weather because my present NMEA 0183 connection between the CP and the GX2200 is using only 2 wires, and I will need to make it bidirectional by adding more connected leads.

To be more accurate, you don't turn it off, but disconnect the output. Then connect the input pair of wires for your desired baud rate.

 

[dave_and_dd]

I believe you DO want to turn it off in the radio and not disconnect the feed from radio to keep the AIS display on th CP. You do need to add the other pair of wires to get the gps to the radio.

This is similar to my setup which works fine. I have a garmin CP but the same radio. AIS shows on the cp, radio gets its gps from the cp.

Dave

 

[Captain Larry-DH]

To be more accurate, you don't turn it off, but disconnect the output. Then connect the input pair of wires for your desired baud rate.

If I disconnect the output I won't receive AIS on the Chartplotter. Section 15.1 of the GX2200 manual details the setting to turn off the internal GPS (required when using an external GPS). I'm going to try turning that off this weekend when I visit the boat, to see if that cures the SOG display issue on my Raymarine speed instrument. (As a test). If so, I'll connect the other NMEA0183 leads from the CP (at another time) to make it bidirectional, and get the GPS signal to the GX2200 from the CP.

 

[mermike]

I believe you DO want to turn it off in the radio and not disconnect the feed from radio to keep the AIS display on th CP.

Yeah, I hadn't had enough coffee yet when I said that. You're correct.

 

[mermike]

This is similar to my setup which works fine. I have a garmin CP but the same radio. AIS shows on the cp, radio gets its gps from the cp.

Dave

This is similar to my setup, a GX2200 and Garmin chartplotter. The GX2200 uses its internal GPS and outputs AIS on the high speed interface, and the chartplotter uses the Garmin GPS. They don't conflict, but I believe I have the Garmin GPS selected as source in the CP.

I really should document all my settings.

 

[Captain Larry-DH]

I went to the boat today and changed the settings on the GX2200 to turn off the internal GPS. No joy, same issue.
I experimented with a few more settings and changed NMEA to 4800 (from 38,400) and changed the corresponding setting on my B&G CP to match the 4800 speed. At 4800 the Raymarine display continued to show SOG when the GX2200 was turned on, but unfortunately the AIS stopped coming through to the CP display. Back where I started.

 

[mermike]

There are different wires for 4800 and 38400 baud. Did you change the output wires?

 

[Captain Larry-DH]

There are different wires for 4800 and 38400 baud. Did you change the output wires?

Nope. You raise a good question.
Page 17, 18 and 19 (and 94) of the manual (wiring diagram with color codes) it appears DSC output wires are 4800, and AIS is always 38400. (DSC and AIS are output on different leads at 4800, but all on one pair of leads if 38400 is chosen). My GX2200 has been set to 38400 and the CP receives AIS on that setting. Does not at 4800, I’ve got to go back and check my wiring.
At 33-degrees today I wasn’t about to start tracing and splicing 22ga leads. Not going sailing anytime soon.