ST290 GPS and NMEA issues

[smorast]

Okay, think we are getting somewhere.

1. The spliced STng to ST2 coming from the ST1 to STng converter has been removed with no negative impact. (What should be placed in the empty socket?)

2. Disconnecting the RED wire from the S3 Course computer ST1 input removed power from the entire system (ST1/ST2). The ST1 RED wire attached to the S3 course computer is the 12V output, not an input. (Appears this needs to remain wired as-is to operate properly). The S3 main power input (40A fused) and the E125 are both engaged at same time by navigation breaker. It appears the E125 was not supplying any voltage to either the ST1 or ST2 devices.

3. Lastly, if the system appears to be working correctly, is there a reason to add a second ST1 to STng converter? There are more than 5 ST1 devices in the system-is it a hard rule that any more than 5 require an additional converter?

Thanks!
smorast

[Chuck - Raymarine - Moderator]

Q1. The spliced STng to ST2 coming from the ST1 to STng converter has been removed with no negative impact. (What should be placed in the empty socket?)

A1. Please attach an updated system diagram to this thread in order that we may determine whether you have now corrected powered and terminated the SeaTalkng and SeaTalk2 backbones.

Q2. Disconnecting the RED wire from the S3 Course computer ST1 input removed power from the entire system (ST1/ST2). The ST1 RED wire attached to the S3 course computer is the 12V output, not an input. (Appears this needs to remain wired as-is to operate properly). The S3 main power input (40A fused) and the E125 are both engaged at same time by navigation breaker. It appears the E125 was not supplying any voltage to either the ST1 or ST2 devices.

A2. As has previously been specified by Steve and has been specified within the FAQ referenced in the response to Q3, the current SeaTalk bus must be disconnected from its present sources of power. Per your original diagram, these power sources were the S3 Autopilot Course Computer's SeaTalk port and the ST290 DPU's SeaTalk port. Correspondingly, the red lead of the SeaTalk cable which is presently connected to the red SeaTalk terminal of the S3 Autopilot Course Computer as well as the red lead of the SeaTalk cable which is presently interfaced to the red SeaTalk terminal of the ST290 DPU must be disconnected. The ST290 DPU must be connected to a 12VDC power circuit via the ST290 DPU's power and ground (not to be confused with SeaTalk) terminals. Failure to make the recommended changes which have been specified within the responses to this thread may result in ground loop, unpredictable performance, product damage and/or reduced product life.

Q3. Lastly, if the system appears to be working correctly, is there a reason to add a second ST1 to STng converter? There are more than 5 ST1 devices in the system-is it a hard rule that any more than 5 require an additional converter?

A3. Failure to divide the present SeaTalk bus into busses of no more than 5 devices and add the recommended additional SeaTalk to SeaTalkng Converters may result in too much current being passed via the single SeaTalk to SeaTalkng Converter. Failure to do so may result in premature failure of the SeaTalk to SeaTalkng Converter as well as underpowering the SeaTalk bus. Please click here to view a FAQ addressing this subject.

[smorast]

First, appreciate the reply.

I would like to reiterate this is my first go around with Raymarine. I would also submit I am at the mercy of the professionals that have previously worked on the system...so please bear with me in resolving their improper installation.

I have attached an updated diagram and documented my proposed solution, which is to eliminate the connection between STng/ST1 network. Then just activate the E125 internal GPS and have two independent systems that are no longer in conflict. Would this suffice to eliminate the issues?

If this path is selected, should the seatalk1 RED 12V and bare wire (currently connected to DPU POWER IN) move to Seatalk1 inputs if S3 provides power?

Is this a technically acceptable solution?

Again, thanks for lending me a hand in trying to remove any issues in the system and making it safe for ocean navigation.

V/R,
smorast

[Steve - Raymarine - Moderator]

I understand what you are looking for, and there are many ways of wiring a system. But we focus on the right way on this forum and have come up with these ways to ensure everything is communicating properly. When you first started your inquiry you stated you weren't get a particular piece of data (LAT/LON) on the ST290. So in order to confirm full communication of equipment, we would recommend we way we explained. If you choose to leave the wiring the way it is, then we will not be able to confirm full communication of data between all the equipment.

It does sound like the system was working adequately with the original wiring, and was providing navigational information.

[smorast]

Thanks, appreciate the candor.

You are correct, my original issue was intermittent lat/long on 290 graphic display. That continues to be the case, but not overly concerned with that as long as other data is correct, which it all appears good to go.

Hopefully, the new diagram provided clarity. I still have a question on DPU power. (See previous post).

As to the original power questions/concerns for stng-st1...in my config, would I see 12v on the st1 side of the center tapped connector? Even if the backbone didn't have a 12v sourced spur?

[Steve - Raymarine - Moderator]

It is not recommended to power the DPU or any other device from the Seatalk bus, because the draw of the DPU (although minimal) could draw the bus power down to cause information transfer issues. The other is if you have an issue with the DPU it could cause the whole Seatalk bus to be taken down. The DPU should be powered by an external input source.

[smorast]

Thanks Steve. Curious, given my diagram, isn't the entire ST2 bus being powered by the DPU?

[Steve - Raymarine - Moderator]

You are not provide adequate power for the system of this size.