[CA] [CA11] Revising system network

[MaMakani2019]

Thanks for your time to resolve the system wiring questions I have!

List of navigation/VHF system products onboard from prior owner:
1. ST60 Wind with R28170 Short Arm Vane
2. ST60 Tri-data
3. ST6000+ controller
4. 300 course computer with Type 2S linear drive
5. Raystar 125 GPS
6. 3015-100 NMEA Bridge
7. C95 MFD
8. 18” Digital Radome
9. AIS650 Transceiver with GPS antenna
10. AIS Splitter 100
11. ST to STng converter for C95 and AIS650
12. Standard Horizon Spectrum GX2350S VHF with DSC
Items 7 through 11 were added in Feb 2014 by prior owner according to Raymarine certificate 201402287498.

I traced the wiring shown in the attached block diagram “Ridenour & Ridenour Wiring 2-2014”. I think the NMEA-SEATALK-NMEA-STng interconnect was not done correctly and may be causing the intermittent GPS signals I see at the MFD. Shouldn't the autopilot should have a separate SEATALK network?

The attached block diagram “Proposed Revised Wiring by Owner” has separate SEATALK networks for the autopilot and ST/STng backbone. SEATALK #1 interconnects The 125 GPS, NMEA Bridge, 300 Course Computer and the ST6000+. VHF GPS Data In is provided by Bridge NMEA Out. 300 Course Computer NMEA is connected to C95 MFD for GPS data. SEATALK #2 interconnects ST60 Wind and Tridata, ST600R, i40 Wind (new component as repeater at Nav Station) and St to STng converter—a total of 5 SEATALK devices. SEATALK #2 connects to C95 via STng and does not carry GPS data. Is this block diagram done correctly?

Power to the VHF, NMEA Bridge, AIS650 and AIS Splitter are from the same C/B so that AIS data is transmitted and distress data available whenever VHF is on. Do you agree this is a good idea? Power to SEATALK #2 devices is from a separate 10 Amp C/B.

Please confirm that I can add an i40 Wind as a repeater at the Nav Station with cable D284 connected to SEATALK#2 as shown in the diagram.

Again, I really appreciate your help as I’m not familiar enough with the available documentation to feel confident about a correct answer. Correctly interconnecting these network protocols is a bit of a challenge.

NOTE: This thread included an updated proposed system diagram.

Cheers
Mark Church

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Mark,

I generally like the changes which you have identified within you latest proposed system diagram. I would however recommend the following changes:

1) There should not be two sources of GPS data within a system having these older components. It is recommended that the GPS receiver having the best view of the skies overhead be used as the system's GPS source. In this case, it is likely to be the RS125 GPS Sensor. If using the RS125, the MFD's Data Sources feature may be used to select it as the system's source of GPS data ... or the MFD's internal GPS receiver may be configured OFF.

2) Rather than connecting connecting the NMEA 0183 input leads of the VHF radio to the NMEA 0183 output port of the SeaTalk/NMEA 0183 bridge, it would typically be recommended that the GPS sensor's NMEA 0183 output leads be connected to both the NMEA 0183 input leads of the VHF radio and to the MFD's NMEA 0183 leads. Doing so will permit the $GP NMEA 0183 talker ID to be included within NMEA 0183 sentences transmitted to the VHF radio and will eliminate a possible failure point within the system.

3) You may want to consider powering the Raystar 125 GPS sensor from the power circuity supplying power to the SeaTalkng / NMEA 2000 backbone rather than from the SeaTalk / NMEA 0183 bridge.

4) The only recommended connections between the VHF radio and the SeaTalk / NMEA 0183 bridge should have been to support NMEA 0183 communications. The VHF radio should neither be powered, nor grounded through the SeaTalk / NMEA 0183 bridge.

5) If following the above listed recommendations, the SeaTalk / NMEA 0183 bridge may be removed from the system and the ST600R may be wired directly to the SeaTalk#1 bus shown within your diagram. When doing so, all three leads of the SeaTalk#1 bus cable should be connected to the autopilot course computer's SeaTalk terminals.

6) The c95 MFD's NMEA 0183 leads (yellow & brown), not its Port #2 input leads, should be interfaced to the Type 300 autopilot course computer's NMEA 0183 input terminals. In this configuration, the system autopilot's Track mode will be supported, as well as its Auto and wind vane mode.

7) The 12V power connection shown in the SeaTalk to SeaTalkng Converter Cable connecting the ST40 instrument to the system should be eliminated. Instead, consider installing a SeaTalkng Power cable and connecting it to one of the unoccupied spur sockets within 5-Way Connector or ST-STng Converter.

[MaMakani2019]

Hi Chuck,

Attached is a revised diagram 3-23-19 which, I hope, has followed your recommendations correctly. Questions:
1) Is NMEA 0183 a balanced signal and therefore the negative wire should be floating and not connected to ground or the shield? I don't want to create ground loops. Also, I expect the shield should only be connected to ground at the source end. For example, the 125 GPS GRN and BWN should or should not be connected to the shield which goes to DC ground only at the GPS end. Same with the NMEA to the 300 Course Computer--ground the shield only at the C95.
2) Should I turn off the C95 internal GPS receiver since I'm using the 125 GPS or will the MFD figure this out?
3) I have 5 C/Bs feeding the system: VHF/AIS, Instruments (powers 125 GPS, SEATALKng and SEATALK #2), Autopilot (also powers SEATALK #1), Chartplotter and Radar. I think this is what you recommended.
4) Your item 7 above refers to an ST40 Wind but I have an i40 Wind. Any problem using this as a repeater on SEATALK #2 since it has a regular SEATALK connector?

Your help is really appreciated. Thanks so much and fair winds to you!
Cheers,
Mark

[Chuck - Raymarine - Moderator]

Mark,

General comments on diagram,

1) It is not recommended that the power leads of a spur cable be tapped as shown to power the RS125. Instead, it is recommended that the circuit to which is powering the SeaTalkng Power Cable also be used to power the RS125.


Q1) Is NMEA 0183 a balanced signal and therefore the negative wire should be floating and not connected to ground or the shield? I don't want to create ground loops. Also, I expect the shield should only be connected to ground at the source end. For example, the 125 GPS GRN and BWN should or should not be connected to the shield which goes to DC ground only at the GPS end. Same with the NMEA to the 300 Course Computer--ground the shield only at the C95.
A1) In most cases, Raymarine products utilize differential RS422 communications. The RS125 GPS Sensor will be an exception.

Q2) Should I turn off the C95 internal GPS receiver since I'm using the 125 GPS or will the MFD figure this out?
A2) The MFD's Data Sources feature may be used to configure which source of GPS data will be utilized by the system.

Q3) I have 5 C/Bs feeding the system: VHF/AIS, Instruments (powers 125 GPS, SEATALKng and SEATALK #2), Autopilot (also powers SEATALK #1), Chartplotter and Radar. I think this is what you recommended.
A3) SeaTalk #2 should be powered from the STng backbone via the ST-STng Converter. Otherwise, this appears to be a good plan for your marine electronics system.

Q4) Your item 7 above refers to an ST40 Wind but I have an i40 Wind. Any problem using this as a repeater on SEATALK #2 since it has a regular SEATALK connector?
Q4) The i40 Wind is simply a ST40 wind with styling changes which match current Raymarine products. It is indeed correct to interface the i40 Wind in the manner shown within your diagram.

[MaMakani2019]

Hi Chuck

Thanks for your review and corrections. Attached is updated diagram 3-25-19.

1) Power source to RS125 GPS has been moved from the spur connector to "Instruments" feed to Nav Station STng converter per your item 1. I believe this also addresses your A3). However, I'm curious if, as an alternative, the SR125 GPS power can come from the SEATALK #2 wiring (red and shield) at the Helm?

Thank you for your excellent input and guidance! I look forward to being able to use the increased system functionality and performance these revisions provide.

Fair winds and safe harbors
Mark

[Chuck - Raymarine - Moderator]

Mark,

Q1. I'm curious if, as an alternative, the SR125 GPS power can come from the SEATALK #2 wiring (red and shield) at the Helm?
A1. As your SeaTalk #2 bus is being powered by the same circuit which is supplying power to the SeaTalkng backbone ... yes.