Raymarine forum

Hello,

I have a issue where the wind on the i70s and the p70s is shown as coming from different directions.

System hardware:
EV400 + p70s
Sail Pack + DST800 + iTC5 + i70s + wind vane/anemometer
There is also a Axiom Pro running the latest version of LH3

Tried so far:
Set both to display apparent wind.

Observations:
The "dumb" wind vane at the top of the mast that is not connected to anything appears to align with the i70s, its the p70s that is considerably different.

I calibrated the EV400 when installed, it was several months later that the Sail Pack was installed, and the sail pack was then calibrated (speed, wind, temperature were all calibrated).

Q: Beyond how to fix this, I would like to know where the wind calibration data is stored? I assume on the iTC5.

Hello Watsala,

This isn't a calibration, setup or software problem, it's that the i70 and p70 aren't displaying exactly the same types of data.

The compass-rose type display of the p70's Graphic page layout always shows True wind direction, since it's related to north in that graphic rather than the vessel's bow. Changing the p70's 'Wind Vane Type' changes how the pilot steers in windvane mode but not the displayed wind data on the Graphic page.

In your image Wind2 you have 4 knots of apparent wind dead on the bow but 6 knots of boatspeed, implying a 2 knot air from astern, which is why you can't see the wind indicator on the pilot display.

In your image Wind1 you have 8 knots of AWS just to port of dead ahead and 5.5 knots of boatspeed implying a true wind on the port bow, which is what the pilot shows. Since you're in Vane mode you can also see the current locked wind angle that the pilot is trying to steer to, 31 degrees Port, which would have been the wind angle (apparent or true, whichever was configured in 'Wind Vane Type' at the time when you entered Vane mode.

If you want to display AWA and AWS on the p70, change to 'Multi' view mode and configure the appropriate data-boxes. You will find that these agree with the i70.

To answer your second question, calibration is always stored in the piece of electronics where the transducer is directly connected: in this case, the ITC5.

Regards,
Tom

Hi Tom,

Thanks for that answer. It makes sense. I will try to put the i70s into True wind mode and see if they agree.

Most helpful as always.

Cheers

W

No problem, let me know if you still have problems.

Tom