[TG] [TG11] Wind transducer wind angle issue

[TKP62]

I have the following:
Newer style wind transducer
i60 Wind display
(2) i70 MF instruments
iTC-5 with all transducers wired to it
(2) P70 autopilot heads
ACU-400 w/EV1
e125

Last season I noticed the wind angle seemed to be off. The system would calculate a 30 degree wind shift (ground wind) after tacking.
I went up the mast and physically held the wind vane to 0 while someone below adjusted the offset within the i70 setup menu. After that and while aloft, I physically held the vane at 90 starboard, 90 port, and 180. While the vane was at 90, at least on one side, the i60 (in AWA mode) and the i70 were showing at least 100+. 180 seemed to be correct.

I just re-launched the boat and re-installed the transducer (I take it off over every winter) and while at the top of the mast I performed the calibration procedure manually by having someone below start the process, then I manually, slowly turned the vane around at least twice to mimic turning the boat in circles. The setup showed "complete" after about 2.5 turns. I then aligned the vane manually to 0 and had the person below complete the function to set zero.

After doing all this, the vane is clearly sending the wrong angle info.
Here is what I got when manually holding the vane at 0-90P-90S-180:
physical position / angle shown on i60 in AWA mode / angle shown on i70 graphic
0 / 0 / 0
90P / 95P / 90P
90S / 110S / 104S
180 / 166 / 166

I tried to take some data at 45P, 45S, 135P, 135S but it's hard to eyeball those angles exactly. I did find that on one of the 45's and 135's, it seemed to be way off (I had the person below tell me when it read those values and it looked like the vane was not at those actual angles)

Clearly the angle is off mostly when reading starboard, and a lot when reading 180.

Could this be related to mimicking doing the circles by turning the vane by hand, or is this a transducer or iTC-5 issue?

[Tom - Raymarine - Moderator]

Hello TKP62,

I think that this FAQ will answer your question.

Regards,
Tom

[TKP62]

Tom,

Thanks for the link. The first doc in the link is for ST60, I have i60 so not sure how to use that.

I will try the pointer calibration in the video shown for the i60, but I do not believe that is the issue.

The displays both show nearly the same angle (i60 analog and i70 digital, both in AWA mode) and the small difference I listed may be due to the person reading them for me.

Let me try to re-explain:

I was at the top of the mast physically moving the transducer wind vane by hand. I can align so the needles point to 0 when I hold the vane at 0, but when I hold the vane at 180, the needles are showing about 166. That is a 14 degree difference between the actual transducer vane angle and what's being displayed. The error seems to vary, but there's an error on nearly all angles except 0.

I don't believe it's a display issue either because the computed GROUND WIND is different when on different tacks. Here's what I mean:
I can be on port tack with an indicated AWA of 70, and the computed ground wind will be, say, 270. If I tack the boat and sail on starboard tack at the same indicated AWA of 70, the ground wind will now be showing computed at 290. That would indicate a 20 degree wind shift, but in reality that wind shift didn't happen. If I tack back to port tack, the ground wind is back to 270.

The system has worked fine previously, it just started doing this last year.

This has to be an error in the angle information the transducer is sending, correct?

[Tom - Raymarine - Moderator]

Hello TKP62,

My apologies, just before your question I had answered another where the poster was seeing different wind angles between digital and analogue displays, and with this in my mind I misread your original question. If the i60 and i70 are reading the same thing, you're correct that this is not i60 pointer calibration (I tend to get a bit heavy-handed on that particular issue because it's usually so hard to persuade people that that really is happening in their system...)

Focussing only on the directly-measured AWA rather than derived/calculated values: when you turn the vane feather slowly by hand, does the AWA on the displays change smoothly and evenly, without seeming to stick/jump/count backwards or similar? I understand that with the discrepancy in angles you're seeing it may well be that the pointer seems to track ahead or behind the vane feather at times, but if it reads smoothly then I don't think there's a windvane fault. You can cross-check this by looking at the signal voltage on the blue and green wires (against the shield/bare of the windvane transducer) with everything connected and powered. You should see on each wire a DC voltage that changes similarly smoothly and evenly between ~2V and ~6V in a sinusoidal pattern, once per rotation of the windvane (the two voltages will be 90 degrees out of step: sine and cosine.) If you see a static or significantly out-of-range voltage with changing wind angle on either wire that implies a windvane (or connection/cabling) fault.

If you see smooth and consistent wind angles/voltages then the problem may be as simple as the display's software linearisation of the wind angle data. If you do a Factory Reset on the i60 (I am assuming that's where the windvane is connected) then that will remove the current linearisation data and allow you to re-do the circles that will re-linearise. The Factory Reset is described in the Dealer Calibration section at the back of the handbook.

Again, sorry I misread your original question.

Tom

[TKP62]

Tom,

The i60 is on STNG with the transducer wired to the iTC-5. I can try the reset and re-linearize but not sure how to reset if doing through iTC-5.

I’m not sure how steady the needle turns when rotating the vane feather. I was up the mast rotating it while a helper was below reading and selecting the calibration settings through the i70 menus.

If I can do a reset, I’ll re-linearize by motoring in circles where I can directly observe the displays. Is it possible that trying to linearize by manually rotating the feather, and maybe not doing it smoothly, that I actually introduced error into the process which is causing the angle error?

Thanks,
Tim

[Tom - Raymarine - Moderator]

Hello TKP62,

Hmm. If the windvane were connected to the i60 then you can reset through its menu, but I'll have to check on resetting wind linearisation on ITC5: it won't be through the i60, would need to be through i70 but I'm not sure that there is an option in the software to do that (I only have the handbook and memory to go on as I'm working offsite and don't have a comparable system here to test with, as I would on my desk.)

No, turning the windvane by hand shouldn't be an issue, this would be little different from a normal linearisation in gusty conditions. I *believe* that the system is simply comparing the sine-cosine curves and smoothing out discrepancies between the two.

Regards,
Tom

[TKP62]

Hi Tom,

I have an update for you and info you can use in the future.

I looked closely at the connector on the transducer arm and saw that there was some copper oxidation (the green "patina") at the bases of the pins and the plastic bottom at the base of the pins. I wire brushed them clean and also the socket on the mount (with all power off!), and went through the linearization (by hand) again along with adjusting the wind angle through the iTC-5. Problem solved! i60 analog and i70 digital displays match the physical position of the vane feather on all cardinal points! The oxidation must have been causing a very minor short throwing the voltage off, thus reporting the wrong angles.

Thanks for your help!

Tim

[Tom - Raymarine - Moderator]

Hi Tim,

Yes, that would do it. I would guess that that sort of problem might normally show up in the voltage measurements we talked about, but perhaps it was a little too subtle for that as yet. Had the tarnishing developed you'd probably have ended up fairly soon with a clearer, no-wind-angle symptom that definitely would have shown up in the voltage measurements.

Thanks for the feedback,
Tom