Expedition Navigation Software 
1 - Fergal
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- From: Galway, Ireland
- Registered: 9/09/2015
- Posts: 159
B and G speed sensor misbehaving
This is slightly off topic but I have confidence that someone on the forum can help me out.
We have a B and G speed sensor (paddle wheel) feeding back to Hydra/Hercules and onwards to Expedition. about two weeks ago we started getting ridiculous readings for BSP - 30 -> 180 Kts. We cleaned out the sensor, made sure everything was installed correctly, but no change. We're seeing these numbers through the system also, so it's not an Expedition calibration table issue.
Anyone got any ideas?
(For tomorrow nights racing I've set Expedition and the mast display to use SOG instead of BSP. But that's not a good fix overall)
Thanks
- DuncanR
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- From: Up and down East Coast Aus
- Registered: 9/16/2015
- Posts: 470
Re: B and G speed sensor misbehaving
In your instruments, what do your measured mile and heel/offset tables say? Perhaps something has gone awry there.
- Fergal
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- From: Galway, Ireland
- Registered: 9/09/2015
- Posts: 159
Re: B and G speed sensor misbehaving
Thanks Duncan. I've looked the time/distance table (measured mile) and saw nothing but I didn't think to look at heel table. I'll check that tomorrow. I also just found something on B&G support pages, hoping this might help:
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Thread Starter- DuncanR
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- From: Up and down East Coast Aus
- Registered: 9/16/2015
- Posts: 470
Re: B and G speed sensor misbehaving
Good find. There is no end the complexities of this game. I swear I'll never be able to "all pretty good and stable now"
- Fergal
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- From: Galway, Ireland
- Registered: 9/09/2015
- Posts: 159
Re: B and G speed sensor misbehaving
Duncan
Just to follow up, that document didn't give me a definitive answer, but it did send me in the right direction. I determined that the calibration factor for the paddlewheel had somehow been set to zero. I'm not sure how this happened and it is making my concerned for the rest of the system. I applied an immediate factor of 6.25 as suggested by the above document (6 blade paddle wheel) and the displayed boat speed numbers were in the right ball park. But a quick check against SOG indicated that they were still inaccurate. So now I have to do a full calibration run to set the correct factor.
I'm just perplexed that the stored value got lost. Hopefully it doesn't indicate a bigger problem.
For now, I'll stop hijacking the Expedition forum with B&G issues!
Fergal.
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Thread Starter- DuncanR
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- From: Up and down East Coast Aus
- Registered: 9/16/2015
- Posts: 470
Re: B and G speed sensor misbehaving
Well done Fergal. I have also lost calibration settings in our elderly instruments, so am absolutely zealous in recording every twist and turn of calibration.
And from my perspective - ahem, I don't speak for Management - no apologies needed. The instruments and Expedition are two parts of one system. I spend as much time on instruments as I do on performance and navigation.
- pjl
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- From: Lake St. Clair, MI
- Registered: 11/09/2015
- Posts: 128
Re: B and G speed sensor misbehaving
Pardon my intrusion, but why are these settings not changing the Exp display values?
- Fergal
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- From: Galway, Ireland
- Registered: 9/09/2015
- Posts: 159
Re: B and G speed sensor misbehaving
pjl
It is not clear what you are asking. Were you trying to post a picture? There are instructions to do that under the General Discussion category
Last edited by Fergal (7/15/2016 10:35 am)
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Thread Starter- ClayAnderson
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- Registered: 8/22/2016
- Posts: 6
Re: B and G speed sensor misbehaving
Wow ! good sharing
- pjl
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- From: Lake St. Clair, MI
- Registered: 11/09/2015
- Posts: 128
Re: B and G speed sensor misbehaving
Slow response to Fergal: - sorry, been sailing too much to do my homework. I have been having instrument calibration issues. Instruments are a mixed bag of Garmin and Nexus, and the Garmin techs admit that their stuff is not real "race" quality in the same league as B&G, so it's a very murky pool of stuff. For example, we sailed the Mac with Bsp about 20-25% off. I run BspSOG delta on stripchart just to tell me how much Kentucky windage I need to apply to the end results. The real point here is that the next race several weeks later, the Bsp was within 2-5%. The mystery is how it got there. I made no known changes to Exp settings.
I had been having unexpected results making adjustments with Exp calibration values to Bsp, and tried to query the Forum on this point with a poor post (see above). Maybe my fat fingering is the problem. It is stated that Bsp is across the table, and the values shown are up to 30k. Why would a sail vessel need calibration of Bsp at 30k for a range of heel values (catamarans, foilers)? I obviously am having a mental block and need help. TIA, pjl