Autohelm ST30 Wind Speed/Direction Problems

[Greg Shakeshaft]

Hello to one and all,
I've done the usual thing. Googled until I'm exhausted trying to find a "fix" for my problem. Then decided that no one appears to have the same thing happen to them so, I have registered with a forum so I can ask and hopefully get some favourable replies. I know what you are thinking... He only joined for that reason. But, you know what, I've never joined a sailing forum before and maybe it was about time anyway

So, back to my issue. I have a ST30 wind speed/direction module fitted aboard my sailboat. It was without its wind cups for a couple of years as the previous set got smashed in a hail storm. I bought a replacement but have only just got around to getting them installed (I needed someone to climb the mast for me). Anyway, the cups are now back on top of the anenometer and are spinning away quite happily however... there is a problem at the display. When I connect the transducer cables to the back of the display it immediately shows the wind speed in knots and also the wind direction (exactly as it should) however within a second or two the wind speed starts to drop (1 knot at a time) until it reaches zero and then after about 3-5 secs the display shows --- which apparently means that it isn't receiving any info from the anenometer. I have checked the cable at the bottom of the mast with an electrical meter and it shows 2 ohms. I have replaced the "through deck" connector incase that was faulty or corroded and I have also made sure that the cable is not damaged from where it enters the deck back to the display itself and I can not see any signs of damage. What really confuses me is why it should work fine when i first connect the wires but then immediately begin to fail. The unit does not give me a reading if i just switch it off and back on. Only the --- is shown.

Any ideas or words of wisdom would be much appreciated.

Cheers, Greg

[Redline452]

Could there be a problem with the power feed to the instrument itself? It sounds like connecting the masthead module is drawing too much power and whatever supply filter caps are discharging. With the module already connected, switching power doesn't let it recharge, only applying power to the instrument without the masthead.

I would measure voltage at the instrument with and without the masthead connected, such as on the Seatalk "pass-through" connector. If there are other Seatalk instruments, try isolating them and powering this one alone.

Another possibility is that it is not ever actually reading windspeed, just responding to a transient glitch when the transducer is first connected, then settling down to zero.

Also, what part of the cable "shows 2 ohms"? Each conductor, end-to-end, or round-trip pairs, or what? That sounds fine for a bare conductor, providing it's not shorted to another, or ground, or anything else, and that the same goes for each wire in the cable. If that's measured through the transducer, it may not mean much, depending on the position and speed of the cups and your meter's response.

You might also try connecting the transducer directly to the instrument, bypassing all the ship's wiring.

Good luck

[chala]

Originally Posted by Greg Shakeshaft

I know what you are thinking... He only joined for that reason. But, you know what, I've never joined a sailing forum before and maybe it was about time anyway
Cheers, Greg

It is for that reason that most people join this forum.
Welcom to the forum Greg.

You may whish to try Raymarine forum. Service and Support or Raymarine Technical Forum

[hzcruiser]

Any luck resolving this, Greg?

I'm asking because I have similar symptoms. Just took down the anemometer to check it separately.

Fair winds,
heinz