Connecting old Garmin to old Raymarine.

Dec 2, 2003
751
Hunter 260 winnipeg, Manitoba
How were you testing for communication between the wind instrument and the Depth/Speed? You are unlikely to get any communication between the two other than for changing lighting intensity adjustment. I.e. the wind instrument can't make use of any of the data from the depth/speed without the Autopilot other than adjusting the lighting level.
 
  • Like
Likes: jssailem
Feb 20, 2016
96
None None None
Twalker:

Regarding your modified sketch. I have iset up pretty much as you show it with the exception of two things. One, the connection between the auto pilot and the depth instrument is a regular Seatalk jumper cable. Second, to avoid a dual power problem, I detached the red wire from the Seatalk bus at the computer. So while I don’t have a yellow and black wire connecting the depth gauge to the auto pilot as you show, have I not acheived the same result by disconnecting the red cable from the Seatalk computer?

As far as the conversation between the depth instrument and the wind instrument, I guess I thought I would get true wind based upon a combination of the boat speed and the wind instrument. I guess you’re saying that a third component is necessary, namely the auto pilot data.

I didn’t check to see whether the lighting was synchronized or not as you suggested.

Thanks again.

Michael
 
Dec 2, 2003
751
Hunter 260 winnipeg, Manitoba
Your configuration should work as well. Power up instruments first using nav switch, followed by the autopilot switch.

True wind needs boat speed - from depth/speed AND boat direction - from flux gate compass attached to autopilot computer.

Adjusting the lighting is just an easy way to make sure that components are talking with each other. There may be other settings changes required in the different instruments to ensure you are getting valid data after they are communicating.
 
Oct 22, 2014
20,993
CAL 35 Cruiser #21 moored EVERETT WA
I have iset up pretty much as you show it with the exception of two things. One, the connection between the auto pilot and the depth instrument is a regular Seatalk jumper cable. Second, to avoid a dual power problem, I detached the red wire from the Seatalk bus at the computer. So while I don’t have a yellow and black wire connecting the depth gauge to the auto pilot as you show, have I not acheived the same result by disconnecting the red cable from the Seatalk computer?
Exploring here. In item "ONE" a Seatalk Jumper cable. Does that have 3 leads? Red - Black - and Yellow? If so the red lead is connected to the AP Controller. The Seatalk jumper cable is providing power to the AP controller.
Noted above that the AP works if the other units are not connected. This implies that the AP computer could be supplying power to the AP controller.

Item TWO Detaching the red wire from the Seatalk bus means the instruments down line from the Computer will not be receiving power but should be transmitting data signals on the Yellow and Ground lines.
 
Dec 2, 2003
751
Hunter 260 winnipeg, Manitoba
If it is a standard jumper cable then yes it should have 3 leads and supply power to controller. First seatalk cable to wind instrument should be a power only with the yellow lead missing as supplied by mfg. so yes - wind, speed/depth and autopilot controller will all receive power with Nav switch activated. By disconnecting the red lead at the autopilot computer seatalk connection it will not receive power and become part of the network until the autopilot switch is activated.

On my system with seperate switches it was necessary to turn on autopilot (computer) after all other instruments to avoid the seatalk failure. - seatalk worked happily on all other instruments without the autopilot being turned on as well.
 
Feb 20, 2016
96
None None None
Twalker

Well, if the jumper between wind and depth is standard, then once you do turn on the autopilot switch would you then have power coming from both ends? From the wind side is one. From the autopilot side is two.
 
Feb 20, 2016
96
None None None
Twalker:

I guess all the switching is just confusing me. Wouldn’t it be true to say that when the auto pilot switch is turned on, what is really happening is that the computer is being powered up, and then the computer in turn is powering up the auto pilot. It really couldn’t be any other way, could it, because there’s only one set of wires on the Seatalk bus and that is a red a black and yellow.

That red line must be feeding directly to the auto pilot.

So that would mean that the power is always going to come over the red sea talk bus wire. If you then feed the Seatalk jumper from the auto pilot over to the depth instrument, then you’ve got power coming from both ends. Once from the auto pilot side, and once from the wind instrument side.
 
Oct 22, 2014
20,993
CAL 35 Cruiser #21 moored EVERETT WA
By George i thin he's got it.
You said you have a "standard Seatalk Cable (yellow/Black/RED)" connecting the depth instrument and the Autopilot. Change that to just Yellow and Black wires not "cable". That is my suggestion.
 
Dec 2, 2003
751
Hunter 260 winnipeg, Manitoba
You stated you disconnected the Red Sea talk wire at the computer yes? That wire supplies power to the “auto pilot control head”. With it disconnected no power goes to the control head or any of the other instruments if you just turn on the “auto pilot switch”. Power will go to the computer, but no further. It is the “autopilot computer” side you are isolating as it provides the power to the motor and takes the most power.

If you turn on just the “navigation switch” it will provide power to the wind, speed/depth and the control head but not to the autopilot computer - control head will act as a repeater for some information (wind/speed/depth) but won’t do anything with the auto pilot as it’s not receiving power.

Further to the right from the seatalk connection on the autopilot computer will be two heavier wires one going to the “autopilot switch” the other going to the negative buss. - it is this connection that provides the power to the computer, drive motor etc.

As mentioned above you could just put in a grey and yellow wire between the depth/speed and the autopilot control head, then reconnect your red wire at the computer. Either this change or how you have it currently should work as long as the “auto pilot switch” is turned on last. - it seems, at least on my system, that the other instruments don’t care if seatalk is running, but the autopilot is smart enough to know it’s connected but not “functioning”.

If it would be less confusing for you - you can change the system to a single switch - but power must be supplied only from the autopilot end. - you would re-connect the red wire at the autopilot and disconnect the non-jumper sea talk connection on the wind instrument.
 
Last edited:
  • Like
Likes: jssailem
Dec 2, 2003
751
Hunter 260 winnipeg, Manitoba
Not sure if it will help clarify or not -

Power
12v + runs on the red wire only - goes to ground (12v -) on the grey wire.

Communications
Runs on yellow wire and also uses the grey wire for ground

Both communication and power require both their respective wires to complete the respective circuit.

The concern is really feeding power along the small wires powering the instruments to provide power to the computer and the drive motor which draws more amps than the instrument wires or their fuse can handle. (& their internal circuits)
 
  • Like
Likes: jssailem
Feb 20, 2016
96
None None None
Twalker:

Let’s assume that the small red wire on the computer is disconnected. If that occurs how is power going to get to the auto pilot? Answer- it comes from the depth instrument via the jumper. But because that jumper is present, the moment that the wind instrument is powered you are simultaneously putting power to the auto pilot. I realize that the computer is not turned on at that moment ( since the “auto pilot switch” is off) but certainly the auto pilot is getting power. Doesn’t that fact defeat your premise which seems to be that you’ve got to start the wind/depth instruments a few seconds before you turn on the auto pilot?
 
Dec 2, 2003
751
Hunter 260 winnipeg, Manitoba
Let’s assume that the small red wire on the computer is disconnected. If that occurs how is power going to get to the auto pilot? There are 2 parts to your autopilot. Answer- it comes from the depth instrument via the jumper. The controller will receive power through the jumper. The “computer” remains unpowered since you disconnected the red wire. But because that jumper is present, the moment that the wind instrument is powered you are simultaneously putting power to the auto pilot. Yes Controller only I realize that the computer is not turned on at that moment ( since the “auto pilot switch” is off) but certainly the auto pilot is getting power. Doesn’t that fact defeat your premise which seems to be that you’ve got to start the wind/depth instruments a few seconds before you turn on the auto pilot? You want to start the other instruments before the computer.


If you wire as i show in my last diagram and as mentioned by jssailem then there will be no power to any portion of the auto pilot when the nav switch is powered on and the autopilot switch is off.

Leaving as you have it the “autopilot controller” - the “display” will have power when the nav switch is on but it can only “talk” to the other instruments - not the “autopilot computer” unless the “autopilot switch “ is on. Without the computer being powered on its like a blue tooth keyboard, mouse and computer display - they may all have power but they don’t and can’t do much until the computer is powered up. The computer is the brain portion that’s giving you the error - not the controller display. It is also the concern for power feed from both ends. It needs to come on last.
 
Feb 20, 2016
96
None None None
I am down at the boat right now.

At the computer, the red wire is disconnected as we discussed.

The wind instrument is connected. The auto pilot is connected. There are two jumpers one from the wind instrument to the depth instrument. The other one is from the depth instrument over to the auto pilot.

When you turn on the navigation switch, all of the screens turn on and the auto pilot says Seatalk failure.

You wait a couple seconds. Then you turn on the auto pilot. And it still says Seatalk failure.

So something is either not connected right or else perhaps there is a defect somewhere in the computer. I don’t know what else to think.

Thanks.

Michael
 
Last edited:
Dec 2, 2003
751
Hunter 260 winnipeg, Manitoba
Something to try as a bit of a test. You mentioned the autopilot worked fine before the wiring changes in stand alone mode?

It could be either a wiring issue or you may have an issue with the control head. I had been going on the assumption it was just wiring.

To test Can you try swapping the two seatalk connections on the back of the control head and give it a try? (Jumper from depth to autopilot is a factory seatalk cable?) What message(s) do you get?

You could also try jumping direct from wind to control head as well. Change jumpers - any change in message after power up?

Also disconnect jumper from control head to depth/wind and reconnect red power seatalk connection at computer - plug in to each socket on control head and power up. - what messages do you get in each configuration?

I’ll see what other info I can get on troubleshooting the control head.
 
Dec 2, 2003
751
Hunter 260 winnipeg, Manitoba
It would be possible to test the network from the course computer as well depending on the results of the other tests.
 
Feb 20, 2016
96
None None None
Thanks.

I was heading back home when your message came through so I wasn’t able to try that set of items. I will try those next week, however

Thanks again.

Michael