Drifting Pressure Signal Flat-Lining Cumulus

[mjferraro22]

My Zephyr weather station pressure readings are drifting, and the pressure sensor is probably corrupt. The readings drift from below 28 psi to above 35 psi relative pressure. When the pressure sensor is between these two readings, the Cumulus software reads from the hardware and is uploaded to my website. When the readings go outside 28 psi and 35 psi, the Cumulus software flat-lines, but is still uploaded to my website. Is there something I can do to Cumulus to ignore these pressure swings and not flat-line?? Thanks.

[mjferraro22]

Forgot to add it is Cumulus 1.9.0 build 958.

[steve]

It discards any values below 900 mb and above 1200 mb as obviously wrong, and uses the previous value. 28 psi is about 1930 mb and 35 psi is about 2413 mb, so I don't understand what you're saying. I also don't understand what it is you expect Cumulus to do when your sensor is clearly broken. Perhaps you could show a graph of what happens, and explain what you would like Cumulus to do instead.

There is a 'pressure spike removal' facility in 1.9.1, but it's not clear to me whether that would do anything for you anyway.

[mjferraro22]

Sorry if I wasn't clear. What I would like Cumulus to do is to ignore the bad pressure readings but pick up all the other good readings like temperature, wind speed, direction, etc. When the pressure reading goes out of bounds, all the readings are frozen. Can I adjust the 900 and 1200 mb limits?? Thanks.

[steve]

Yes, sorry, I should have realised you were talking about all the other readings. At the moment I'm afraid I can't think of anything you can do. At some point I do intend to allow the 'extreme' values to be configured and an option to not discard all the data when just one reading is out of range.

[steve]

As a quick hack, in the next build I've made the 900 and 1200 pressure limits configurable via the cumulus.ini file.

[mjferraro22]

Is that build available or will it be part of 2.0??

[steve]

It will be the next build of 1.9.1 beta. I'm waiting for a fix for a third-party component that I use before I release it; hopefully it won't be too long.

[mjferraro22]

I see that 1.9.1 is now available. Is the fix you mentioned available in the cumulus.ini file??

Let me know. Thanks.

[steve]

I'd completely forgotten about this. The fix was already in the code when I first mentioned it, and available for download a few days later; the extremes can be configured using EWminpressureMB and EWmaxpressureMB in the [Station] section in cumulus.ini. But looking at the code now, I see that I have made an error. I've only changed the code to use the configured limits in the two cases of data from the logger, and 'live' data when external sensor contact is lost. In the 'normal' case (live data, sensor contact not lost) it still uses 900 and 1200.

It would have been helpful if you had actually tried the beta, then we would have found the bug and could have easily fixed it. I've fixed it for the next build, but I don't know when that will be available.

[mjferraro22]

Just checking back in with you. Were you able to address my pressure issue in C2?? If so, I will load it up and try it out. Let me know. Thanks.
Mike Ferraro

[steve]

Were you able to address my pressure issue in C2??

You've misunderstood; I haven't done any work on Cumulus 2 for a very long time. The fix is in the next build of Cumulus 1, which will be a beta version called 1.9.2, and I'll announce it when it's available - I have a lot of other changes to make before I do that. You'll see the announcement when I do it, so there's no need for you to keep asking whether it's available yet.

[mjferraro22]

Steve-
I see that 1.9.2 is available, but I did not see in the announcement that this issue was addressed. Let me know. Thanks.
Mike Ferraro

[steve]

Yes; as I said, the fix was in the the first release of 1.9.2.