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Full Version: ST50 Speed instrument compatible with CruzPro SOG-1?
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I'd like to avoid a paddlewheel sensor and so am considering using a CruzPro "SOG-1 paddlewheel converter" (http://cruzpro.com/sog1.html) to provide a speed signal to an ST50 Speed instrument, which would then be connected via SeaTalk to an ST50 Wind instrument.

I understand that the SOG-1 takes a GPS NMEA 0183 speed signal and converts it into a 22,000 pulses per nautical mile format that would normally come from a paddlewheel type sensor.

I'm hoping that this arrangement will enable the ST50 Wind instrument to display true wind, which it needs speed information to do. (Of course this speed information will be speed over ground, rather than speed through the water, but that's fine with me in terms of computing true wind.)

I'm also hoping that by connecting the ST50 Wind to the ST50 Speed via Seatalk that the Speed instrument will then be able to display VMG.

Q. Do you know if the ST50 Speed instrument normally uses a speed transducer that outputs 22,000 pulses per nautical mile, which I understand is an industry standard, and which would then make it compatible with the CruzPro SOG-1?
Welcome to the Raymarine Forum kevkal,

Please click here to view a FAQ addressing True Wind ... pay particular attention to the link within the FAQ providing access to a white paper on this subject. While "fooling" the system with data derived from SOG instead of speed through water may permit the True Wind data items to be populated within the system, the resulting True Wind values and features dependent upon True Wind will not be representative.

The information which you have requested regarding the transducer's design is beyond the scope of the support offered. However, please note that the instrument speed through water transducers sold by Raymarine are produced by Airmar, Inc. who may be able to supply you with the requested information.
Very much appreciate the information, and its accuracy.

Thank you!
You're welcome.
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