Airmar PB200
Originated by: Tom Wilson (SUNY), Friday August 12, 2011
Originated by Thomas Wilson (SUNYSB) on Friday, Aug 12, 2011
Speaking of alternatives to RM Young,does anyone have experience with the
Airmar PB200? It's $1,000 street price and has outputs of apparent AND
true wind along with DGPS, heading, barometric pressure, air temperature,
and wind chill. It even has a rate gyro and acelerometer to improve wind
measurements when we're rocking and rolling out there.
Our R/V Seawolf has the earlier PB150 model which has held up for several
years so it seems robust enough. The PB200 might be a real deal if the
accuracy is sufficient.
http://www.airmartechnology.com/2009/products/marine-product.asp?prodid=105
Tom
Reply From Robbie Llaird (WHOI) on August 15, 2011
The Airmar wind sensors look interesting, but I have one concern. The
oceanographic community has used sensors with magnetic compasses in them in the
past. It's my understanding, (and note that I was not involved, but this is
what I've been told), that they don't work well on ships, at least not the ones
we have. WHOI took the compasses out of the IMET wind instruments years ago,
because they did not work well. Unless you install soft iron and compensating
magnets, compasses on ships are only good for the general area where they were
originally compensated. I know that the newer electronic compasses can do some
magic with compensating for deviation, but have to wonder if the system would
need to be re-compensated if the ship was to travel for a large distance. Plus
there are other issues with magnetic compasses, like staying on the same heading
for days at a time causing additional temporary changes in the deviation. And
putting steel vans on deck, etc.. It would be great it these could work, but
I'm somewhat sceptical.
Robbie Laird
WHOI/SSSG
Reply From: Shawn R. Smith (FSU) on August 17, 2011
Hello all,
I agree completely with Robbie's comments concerning magnetic compasses in wind sensors. Throughout the past 15 years, the FSU RV data center has received wind data from a number of vessels that have deployed magnetic compasses (including the earlier IMETs mentioned below), and the compass measurements were frequently unreliable. I too would be suspect of the operation of the Airmar all-in-one sensor on an RV.
Shawn
SAMOS Data Center