A28106 Low Speed Paddlewheel?

[walmsleyc]

I have a ST800-P120 transducer for my ST60 instruments on my 35'sailboat. I have noticed that there is a low speed paddlewheel available (part #:A28106).

Is this a worthwhile upgrade for low speed accuracy?

Chris

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum walmsleyc,

As speed through water sensors have non-linear error, I suspect that you will find that the greatest increases in speed through water accuracy are associated with instruments supporting multi-point calibration (ex. i70S Multifunction Instrument Displays) as opposed to the single point calibration supported by i50 (and ST60) Speed/Tridata Instruments. While is it conceivable that the wider, flatter surfaces of the A28106 replacement paddlewheel provide more surface area to permit greater rotational force on the paddlewheel's vanes, relatively few are sold. You may want to check with some performance sailing forums to determine whether any significant gains have been reported in conjunction with paddlewheels having the wider, flatter surfaces of the A28106 replacement paddlewheel. This paddlewheel was applicable to speed/temp transducers designed for use with the long retired ST50 instruments.

[walmsleyc]

Thanks. I haven't found many references to it at all. In examining it at a local shop, it doesn't look like it would even fit the ST800-P120. The overall diameter looks too big. Are you able to confirm which transducer models it would even work with.

Chris

[Chuck - Raymarine - Moderator]

This paddlewheel was applicable to speed/temp transducers designed for use with the long retired ST50 instruments. As Raymarine Inc. no longer sells parts for ST50/50+ instruments, it is recommended that Airmar, Inc. be contacted for information on the applicability of this part manufactured by Airmar.