Autohelm ST50 Wind Instrument ??

[PlumBob]

dougweibel, it does indeed have multiple wires. That's interesting that it may have a 4-phase signal coming down from the direction transducer. There is a place where that cable is spliced - I know that from having pulled the mast a couple of times - so I can get to the wires. Problem is, I don't know which ones carry the direction signal. Will look into that, tho.

THANKS.

PB

[thunderhoof]

Most likely the wires in the mast are for power, power return and (2) NEMA 0183 (could be NEMA 2000 in a recent unit) so heading is already processed before being sent down the mast.
From my experience there are two pickups at 90 degree azimuth separation mounted inside the part that holds the wind and speed sensors. I would bring the unit down and try orienting the pickup in 90 degree steps.

You should be able to find the correct cable at a marine installer near you. They have many left over pieces from other installations and you do not need a full length cable alth in the mast.ough I suggest you replace the cable if it is not a single wire

[thunderhoof]

Sorry...although I suggest you replace the cable if it is not a single wire in the mast.

[Capn Dan]

PB,
When you do the two circles, you are linearizing the unit, not aligning the needle. Linearization is done when you have a new unit. It will not do it again unless you do a master reset.


You said "" "semi-consistently …"" This actually sounds like your masthead transducer is bad. When one directional sensor is out, you will see the needle move through maybe 180 degrees and then jump and even go backward. Take the boat out and do a 360. Look for the needle to make a smooth 360 degree rotation. If it jumps or backs up, the masthead transducer is most likely the problem.


If you can go into the calibration mode and adjust the needle but the change is not stored, you probably have a bad memory chip in the ST50 head.


It was mentioned that you could simply move the vane on the masthead transducer. Some of the ST50 transducers did have a flat spot on them, but most did not so moving the vane might be an option.


I repair older Autohelm and Raymarine instruments and autopilots. Fell free to contact me through the CF link.

[RodrigoDC]

Capn Dan,


I may bother you with a question or two as well. I will be replacing my ST50 Wind Display Unit as my new (old) boat has a display that is not working (or at least it does not turn itself on).


I am hoping to replace the display and that the transducer works well (from the cockpit, the vane seems to turn freely, and replacing the cabling is just too much of a challenge when I have to repair the engine and so many other higher priority shores).


So, once I replace the display from eBay, I will need to calibrate it, and should I run into trouble, I'll report back.


Thank you all for your wonderful suggestions.

[Ssas5342]

RodrigoDC, I have exactly the same problem with my ST50. Same symptoms as yours. I have replaced the transducer with a new one, replaced the display unit with a second hand one from a friend that was working when he updated it. Still the problem persists.
I’m thinking it could be the wiring in the mast as it is probably original from 1996.
Capn Dan. Are we able to do a factory reset to see if this fixes the problem?

[sailah]

Not sure if this is applicable but my raymarine wind transducer was locked on a specific heading no matter which way I turned the boat or where the wind was coming from. I tested it according the the raymarine forum and it's pretty simple to do. You can check at the mast where the wires go to junction box or at the display. I had mine removed for the winter so I tested it on my desk. You need someway to feed it 8V, I used an Agilent power supply.

I was not getting the correct readings from the hall sensor so I found the manufacturer and bought a couple for $5. Soldered in replacement and it works awesome.

https://www.youtube.com/watch?v=qAEUHWjrMMQ

[sailah]

https://forum.raymarine.com/showthread.php?tid=97

This is the hall effect sensor part that you would need if your transducer fails the tests

https://www.mouser.com/ProductDetail...204KDCABA002SP

[Capn Dan]

The above sensor change is for the late model ST60 transducer. Although that transducer will work with a st50 head, the speed will not be correct and you cannot adjust for that in the ST50 heads. You can adjust the speed factor in the ST60 heads.

5342 -- you cannot do a factory reset in the st50, only the st60. If you want your ST50 heads or transducers tested, contact me through C.F.

[Ssas5342]

Originally Posted by Capn Dan

The above sensor change is for the late model ST60 transducer. Although that transducer will work with a st50 head, the speed will not be correct and you cannot adjust for that in the ST50 heads. You can adjust the speed factor in the ST60 heads.

5342 -- you cannot do a factory reset in the st50, only the st60. If you want your ST50 heads or transducers tested, contact me through C.F.

Thanks Cap, but I’m in Australia. I’ll do some testing and see what I come up with.

[Mr B]

Following,

[danvon]

Evening all. I am having an issue with my ST50 wind instrument where the wind direction needle seems to get stuck. I can sometimes tap the instrument and get it moving but it will not point closer than about 90 to the wind on either tack. I am getting the appropriate voltages down from the mast on the blue & green wires. This really seems like a mechanical issue - does it sounds familiar to anyone?


Thanks in advance.

[SaltyMetals]

Danvon, i had same prblm with mine. After bringing it down from the masthead i stripped it and cleaned the bearings. You will find some guidance on YouTube. Very simply the bearings had gone dry and a little rusty after 15 years. I also found some human hair caught in the anenometer and the direction needle which did not help. So I cleaned and oiled the bearings and put it all back together. For some versions there is a refurb kit which includes new bearings but my Raymarine unit was too old (2003) so no refurb kit existed. You could buy a new unit but that is expensive and my self-refurbed unit has now been working w no problems for the last 3 yrs.
Andrew
"Gernial Bee"

[danvon]

Thanks for the response, Andrew. I guess I was a little unclear in my post. The problem seems to be at the display head, not the masthead transducer (in fact I replaced the transducer with a different used unit, and verified that everything spins as it should etc. It also returns voltages down the mast that are in the range that they should be).



The problem seems to be that the needle on the display head is somehow hanging up, as it seems to get "stuck" and sometimes can be freed by tapping the case. I saw one reference to the units heating up in the sun and causing the needle to stick. That was in an Amazon review of all paces, and I cannot find anything else about it. My issue does not seem obviously temperature-related. Maybe a bad bearing in the display head?



I'd love to get at least a little guidance before I dismantle the unit, which seems non-trivial. But that may be the option here.