Magnetic Heading Sensor Round-up

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jimh
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Magnetic Heading Sensor Round-up

Postby jimh » Wed Mar 01, 2017 8:29 am

MAGNETIC HEADING SENSOR ROUND-UP

Here is a short list of NMEA-2000 magnetic heading sensors available now:

SIMRAD
The PRECISION-9 compass is the top model at $645. In addition to heading it also outputs rate-of-turn, roll, pitch, and heave. The heave output when used with certain Simrad echosounders can remove the effect of wave action on the SONAR depth display. (It can remove the wavy bottom contour created by wave action on the vessel changing the distance to the sea bottom.) Heading accuracy is said to be ±2° and data rate is 10-Hz.
http://www.simrad-yachting.com/en-us/Products/Compasses/Simrad-Precision-9-Compass-en-us.aspx

The RC-42 Rate Compass is an older design and sells for $679. The heading sensor design is referred to as a flux-gate compass.
http://www.simrad-yachting.com/en-US/Products/Compasses/RC42-Rate-Compass-en-us.aspx


LOWRANCE
The POINT-1 heading sensor is also combined with a GNSS receiver for $200. This dual purpose design can create installation problems as the two devices may work best in different locations. There is also a variation called the POINT-1AP that is bundled with the OUTBOARD PILOT auto-pilot product. The AP model has different dampening to optimize it for steering an auto-pilot. Heading accuracy is said to be ±3° and data rate is 10-Hz.
http://www.lowrance.com/en-US/Products/NMEA-2000/Point-1-en-us.aspx

Lowrance also sells the PRECISION-9 at $645. It appears to be the same as the SIMRAD version. (I'd buy the Simrad unless you could save a fortune on the Lowrance-branded model.)
http://www.lowrance.com/en-US/Products/NMEA-2000/Precision-9-Compass.aspx

GARMIN
Garmin has two heading sensor products which are just now announced and new to the market.

The STEADYCAST heading sensor is $150. This is a miminalist product that outputs only heading.
https://buy.garmin.com/en-US/US/p/572462?zebratwo=CJ#devices

The 9-AXIS heading sensor is $650. This top-end product outputs heading, rate-of-turn, trim [pitch], and heel [roll]. Heading accuracy is said to be ±2° and data rate is 10-Hz.
https://buy.garmin.com/en-US/US/p/572463?zebratwo=CJ

COMPATABILITY
Magnetic heading sensors typically require calibration to apply compensation for the particular magnetic environment they are installed into, and typically the calibration routine is implemented by a multi-function NMEA-2000 display on the same network and of the same brand as the sensor. For this reason there is likely to be a strong preference to match the heading sensor brand to the multi-function display brand. Some sensors can self-calibrate if they detect certain conditions, such as time from power-up and piloting a course of a certain rate of turn and making several circles.