[CA] [CA11] iTC-5 rudder angle compatability

[cottingame]

I have a 2002 motor vessel that was originally equipped with Raymarine ST60 SeaTalk1 electronics and Type 400G (S3)/ST7001+ autopilot. Most electronics have now been updated to NMEA 2000. Only the wind sensor, LifeTag, and autopilot SeaTalk1 components remain. I have used Raymarine iTC-5 and SeaTalk1 to SeaTalkNG converter to successfully pass the wind sensor data to the NMEA 2000 bus. (The SeaTalk1/SeaTalkNG converter is inserted in the NMEA 2000 bus via SeaTalkNG to NMEA 2000 cables.) However I am not having any success passing the rudder angle data to the NMEA 2000 bus. The iTC-5 rudder LED indicates no connection for the M81105 rudder angle transducer when the leads are properly connected to the iTC-5. However when the rudder angle transducer is connected to the Type 400G course computer the rudder angle is properly displayed on the ST7001+ autopilot control unit display. I have tested for both continuity and shorts in the leads. I have connected the rudder angle transducer leads both directly to the iTC-5 and in parallel with the 400G course computer. In all cases the rudder angle is properly displayed on the ST7001+ while the rudder LED on the iTC-5 continues to slowly flash indicating no connection.
The i70s Instrument Installation & Operation Instructions (81364-1) pp. 103 indicates that the M81105 rudder reference is compatible with SeaTalkNG when connected using an iTC-5. So why is the iTC-5 not recognizing the rudder angle connection?

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum cottingame,

Short answer: the rudder reference transducer must be directly connected to the autopilot's course computer within systems featuring a S1/S1G/S2/S2G/S3/S3G autopilot course computer.

Within systems featuring a Raymarine autopilot design which precedes the Evolution autopilots, the rudder reference transducer must be interfaced directly to the autopilot's course computer. The feature which you are attempting to utilize was designed for use within systems lacking a Raymarine autopilot where rudder angle data is desired. When utilizing the latter, the rudder reference transducer must be calibrated via an i70S/i70 MFID or retired ST70 MFID.