Autopilot 12V cabling

[Diga]

Hi,

I am about to install a Raymarine smartpilot w/ linear drive in my Bav 36 (04). I would appreciate some advice on how to do the right 12V cabling. Any pictures and/or drawings would be excellent.

Thanks in advance,
Bo

[Lyra]

I have the same boat but took the route of replacing the ST4000+ wheel mounted drive by installing only the linear drive and remaining with the ST4000+ head - so the cabling was a bit different. I believe the Smartpilot would be easier.
What configuration do you have - 1 or 2 aft cabins? If it is the 2 cabins I can share my thoughts.
What Autopilot do you have now? how is it wired now?
 

[tiger79]

Follow Raymarine's installation instructions to the letter and you'll have no problems.  In particular, ensure you use the correct power cable size, as recommended by Raymarine.  If your power cable length is close to the limit of one size, use the next size up.

You can get a tiller lever from Jefa.

[Diga]

I have the 2 aft cabin version. There is no autopilot installed, so no wiring done yet. I am in doubt how to connect to the battery and/or the panel.

[tiger79]

I have the 2 aft cabin version. There is no autopilot installed, so no wiring done yet. I am in doubt how to connect to the battery and/or the panel.

You can connect it direct to the main services switch, but with an appropriate fuse close to the switch, to protect the wiring.

[Lyra]

Most likely circuits 18-20 on your panel are spare.
One of them (don't remember which) is rated at 20Amp so you can connect the system to it.
You will have to route the main power cable from the panel towards the underseat at the entrance to the cabin - this is a bit tricky, but from there it is quite easy to route it under the bed, at the side close to the center of the boat all the way to the back.
You can mount the computer unit and the compass on the rear bulkhead.
For the linear drive you will probably have to build a "bench" because the small tiller should be facing aft - the recommended length for the tiller does not allow installing it facing forward. I think someone in this forum installed it on the rear bulkhead but from what I measured this would mean a tiller with a shorter than recommended arm length.
The rudder position sensor can be installed on the port side also with some kind of a shelf attached to the bulkhead.
The cable from the computer to the control head i easily routed from the back, to where the steering cables go and up to the wheel.

[Diga]

Thank you for your very helpful advice 

[Spirit of Mary]

I have the same boat but took the route of replacing the ST4000+ wheel mounted drive by installing only the linear drive and remaining with the ST4000+ head - so the cabling was a bit different. I believe the Smartpilot would be easier.
What configuration do you have - 1 or 2 aft cabins? If it is the 2 cabins I can share my thoughts.
What Autopilot do you have now? how is it wired now?

Hi,
I have also the ST 4000+ instrument, which I think is at the same time the course computer. How does the ST4000 cope with the much higher Amps from the linear drive? I have the linear drive Type 1 installed and also still the ST 4000 instrument but no operation experience yet. My plan was to install the ST6000 instrument with the belonging course computer. But when I don't need it saves me a lot of costs. My boat is a Bav 38.

[Salty]

The ST4000 instrument, if it's anything like the wheel pilot system I have, merely instructs the course computer of the course you want to steer, it doesn't supply current to your linear drive or in my case to my wheel pilot drive motor, and does not have to cope with the high amperage needed by those drive systems. The course computer decides how it will arrive at and maintain that course, and it, the course computer that is, sends the necessary current to the linear drive or in my case to the drive motor to steer the boat to the course your ST4000 instrument has instructed. The course computer has its own 12volt power supply which comes from a suitable source such as switches 18-20 on your electric distribution panel as Lyra has suggested. Your ST4000 instrument is connected also to the course computer via its own dedicated Seatalk connections which will also connect to your wind, depth and speed instruments. Assuming you are fitting a Raymarine autopilot system, you will get with it a full instruction on how the system is wired together. As I and others have said, follow that instruction implicitly and you will be rewarded with a system that really works well. All you need to do is to determine where you will take your heavy 12volt current from to go to your course computer and from there on to power your linear drive. It is in fact quite an easy system to fit so long as you follow the Raymarine guideline. If you are unsure of your own ability in regard to the electrical wiring, then for your own safety and for the safety of others who may be affected by any malfunction of your system, then the best thing you can do would be to bite the bullet and employ a recommended marine electronics firm to fit the cabling, at least as far as between the main distribution panel and the course computer.

[Symphony]

As suggested take the power from the main panel. Mount the fluxgate compass in the hanging locker in the starboard panel and the computer unit on the inboard bulkhead in the cabin directly below the access hatch to the underside of the binnacle. This makes the wiring runs easy as it is all in the one cabin. Some do mount the compass on the aft bulkhead but the Raymarine instructions suggest it is best near the centre of the boat, so most I have seen are in the locker. Just make sure you do not stow anything metallic in that locker - but it is for clothes which are not a problem.

[Lyra]

How does the ST4000 cope with the much higher Amps from the linear drive?

No problems after several months of operation. I also confirmed this with Raymarine some years ago - good enough for type 1 (not for type 2).
Make sure to use proper cable gauge because the cables go first all the way from the panel to the control unit, nearly 8 meters with proper routing, and then goes from there to the drive - another 3 meters.
During setup you should select the ST5000 option - this information appears nowhere in the ST4000+ manual but you get it as one of the options during dealer setup.

But when I don't need it saves me a lot of costs.

This was exactly my calculation. If I remember the numbers correctly the drive alone costs about 1K USD less than a complete kit, and buying the components separately is about 200 USD more than the kit. So based on the information that I got I decided to go for the drive only, and at most purchase the remaining parts later if this did not work.

The ST4000 instrument, if it's anything like the wheel pilot system I have, merely instructs the course computer of the course you want to steer, it doesn't supply current to your linear drive or in my case to my wheel pilot drive motor

As a standard the ST4000+ does not have a separate course computer and the control unit (which AFAIK is hardware identical to the 4000 and the 5000) contains also the power circuit to drive the motor (originally, as can be seen from the manual, it was designed only for the wheel drive or the small tiller drive)
Is your system configured differently (interface of a 4000 head to a separate course computer - did not know that this can be done)

Raymarine instructions suggest it is best near the centre of the boat

Actually what the manual says is to find the center for minimal pitch and roll movement, and locates it at the boat center line and 0.3-0.5 boat length from aft - so I guess that the locker location is a compromise - closer to the side than the center line, and also my aft bulkhead installation a compromise - near the center line but very close to the aft. To meet this recommendation I think the best location is the bulkhead between aft cabin and engine compartment very close to the ceiling. Although it is visible over there it is out of the way (I installed at that location a much larger solar charger).

[Salty]

On my B36(2002) I mounted the the flux gate compass in the space behind the back of the starboard settee on the transverse double bulkhead just forward of the chart desk. This area was chosen being near to the mid length of the boat where it would be least affected by any pitching movements, though ideally I'd have preferred it to have been as near as possible to the centreline of the boat. I did want it to be hidden away rather than in my face, and I did not want it to be within any bilge area or near to other machinery or electronics. The course computer was placed on the transverse bulkhead within the starboard aft cabin hanging locker, and the connecting wiring was taken under the berth in that cabin and outboard of the fuel tank until it reached the lazarette. From there the wiring was taken up and into the area below the steering pedestal, and on to the instrument panel to join up with the course controller. The power for the steering motor was taken from the course computer along with the other cables referred to above. On the 12volt distribution panel I used one or other of the two switches referred to in an earlier posting for switching the autopilot on/off. On test before taking the boat out I needed to switch the black and red wires for the motor over where they connected to the course computer, in order for it to operate in the correct sense, i.e., starboard rudder for a starboard turn. Thereafter follow the Raymarine instructions for the system to auto learn how to steer your boat. In use I have found with my wheelpilot that the sensitivity needed to be reduced down to setting number three where it copes very well with most of the kind of weather that I'm happy to sail in. One disadvantage of the wheelpilot is that it is quite noisy in use, so I may well change it to a below deck system, though I'm not in any hurry to change it. Apart from that the difference it has made for me sailing single handed, is immeasurable.

[Spirit of Mary]

It was also my opinion (like Lira) that the ST4000 wheelpilot system doesn't use a separate course computer.
It came new (2003) with the boat but was not used the first 5 years when the boat was used by a sailing school. They said that it never functioned well. When I bought the boat in 2008, I experienced a lot with the settings but couldn't get it right. I even installed a rudder reference meter. After I got (from a Dutch Bavaria forum) a one page instruction about the settings, from which one was the ST5000 selection option, it worked reasonable.
However I also found that on my Bav 38, with the sails trimmed optimal, that with wind force 5 and beyond it is not strong enough. Also I like to take the wheel off when in the marina or at anchor, which is not good for the plug connection of the wheelpilot drive motor. Therefor the installation of the below deck linear drive Type 1.
But at the more heavy weather conditions the higher amps of the linear drive are required! I also want to use the external Gyro for the steering, which is now used for my radar and chart plotter.