More ST70, & the calibration conundrum
Thanks to a loan by the good John Gass of his test SeaTalk wind sensor, I’ve now got a Raymarine ST70 Wind Pod plugged into the lab’s ever expanding NMEA 2000 experiment. The Pod can supposedly gateway “any standard Raymarine wind transducer” onto SeaTalkNG and it was pleasing to see that it does indeed put out a standard NMEA 2000 Wind Data message (PGN 13036). All the displays read it fine. And, as suggested above, the ST70 has splendid graphic calibration and diagnostic facilities that work with the pod and sensor. You can correct the vane offset and apply a speed correction factor, either via an underway guided routine or manually. The ST70 can also query the components for model and serial numbers, software and hardware editions, even node voltage.
All that calibration happens over the network but that does not mean that the process is standardized and hence cross-manufacturer like the data is. The Maretron DSM250 instrument can not calibrate the SeaTalk wind sensor, and the ST70 can not calibrate the Maretron wind sensor, though either will show wind data from either sensor. I wrote a long comment about this recently, and it will surely be an ongoing issue for people trying to mix things up a bit. One thing to note is that the calibration lives in the sensor; you can, for example, set everything up with the ST70, unplug it, and all the displays will still see calibrated data. So I suppose an installer can use his own Maretron DSM250 or ST70 to setup sensors, but that means a trip back to a yard if you need to re-calibrate. As I wrote in that comment, this conundrum is is pretty much the way it is with all NMEA 2000 gear right now, though there’s hope that at least simple calibrations will become standardized. In fact, further down that thread you’ll see chatter about the Garmin GMI 10’s ability to calibrate other manufacturer’s gear. Well, I just got one hooked up and, by gosh, it will set a keel offset on the Maretron DST100, but that’s it, and that depth/speed/temp sensor has three other possible calibrations. The GMI is neat, more next week, but definitely running first generation software. The screen below, full size here, was taken before the GMI was added but does show what sensors are on the network and the ST70 Pod in action.