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Pressure is acting oddly
Posted: Thu Jan 03, 2019 10:36 pm
by Ag2000CO
Winter is being hard on my equipment! Last month the temp/hum sensor on my Davis PWS died (stops reporting when the temp drops below 2.1°F.) Parts on order.
Now the atmospheric pressure has developed a "bump" at 30.69-31.16inHg; see graph below. This sensor is internal to the MB, so here I am. I have had the MB sense Jun 2017. Replaced the USB RAM in Aug 2018. Other than that the MB has worked fine out of the box. Current system:
Platform: Meteobridge PRO *
RAM: 61500 kB total, 10268 kB free (83% used)
Storage ATP: Internal 7028 MB total, 6995 MB free (0% used)
SW Version: Meteobridge 3.8 (Dec 16 2018, build 12584), FW 1.4
Uptime: 17 days, 23 hours, 23 minutes Buffer: 1 items (0%)
Power Data: 5.49V 413mA 2.27W (Box Climate: 51.5°C 3%)
Is the sensor bad? Is it replaceable?

Re: Pressure is acting oddly
Posted: Thu Jan 03, 2019 11:00 pm
by Ag2000CO
More analysis not able from the graphics. This has only happened on 2 and 3 Jan 19 (shown).
Both days pressure reading returns "at the same time" as the temp returns to operation. Coincidence??
Davis unit is connected wirelessly to the MB Pro (No davis console). MB is sitting in a window with line of sight to the PWS. I do have a sun shade to keep direct sunlight off of the MB (SE facing window). When new I was distressed by the MB high internal temperature.
Re: Pressure is acting oddly
Posted: Fri Jan 04, 2019 3:39 am
by Mattk
High internal temperature is typical of being inside a small enclosed alloy box, not a lot can be done with that.
As for the dropout one would suspect a reception issue and/or sensor issue based on the outage followed by such a straight trend? What is the distance between the MB and outside sensors? How this relates to pressure is the interesting one?
Re: Pressure is acting oddly
Posted: Fri Jan 04, 2019 5:06 am
by Ag2000CO
"What we have, is a failure to communicate." Sorry. I included what
I think are unrelated event just to give a 'complete history' of the MB/system. (Spent too many years in maintenance when the operator would forget to mention that the antenna was hit, but "we fixed it with duct tape!")
The issue with the temp/hum sensor has already been worked with Davis Inc and Boris.
Distance between units is 20-30 feet and signals are reported in the range of -53db to -59db, even when the temp sensor freezes. RF Sens. is set to -75db.
The pressure problem is the issue. I do not think the internal pressure sensor issue is related to the external temp sensor issue. For 1 the temp issue started the end of November, and occurs when the temp is below 2°F, which made it hard to analyze with only a few examples mostly in the middle of the night. The pressure issue has only occurred twice (2 & 3 Jan).
This morning (4 Jan, 07:40) the temp again dropped below 2.1°F for 6 minutes. At the same time the pressure was also above/at the same level that the "bump" occurred before. Don't know if this means anything, it is just a data point.

Re: Pressure is acting oddly
Posted: Mon Jan 14, 2019 10:30 pm
by Ag2000CO
The weirdness continues. On 9 Jan 19, replaced the Temp/hum sensor on my PWS, and did a power restart on the MB which updated the SW to 3.9.
The first night after update the Solar level became stuck at ~600W/qm I reverted to 3.8 to no affect. Looking at the history, sol0rad, some times just the average at night is ~600W/qm some times average, min and max are different 600 something readings.
I think it is unrelated, but note that the Temp/hum is not working again. The first night after the update that the temp dropped below 0°F all was well. The next night and after the original problem returned. The failure now occurs at 0°F. Before failure was at 2.1°F
I have not seen a recurrence of the odd pressure readings. This cascading failure is getting hard to fix between snow storms. Any suggestions? Calling Davis

Re: Pressure is acting oddly
Posted: Tue Jan 15, 2019 12:29 am
by Ag2000CO
Having replaced all the related Davis hardware (Transmitter and Temp/hum sensor) what have been the firmware updates?
The problem with Solar rad reading/history started when the system updated to 3.9 and continues after returning to 3.8
The first issue with temperature started around 25 Nov 2018. That was the first time this season that the temperature dropped below zero. Looking at other history (Weather Underground) last jan-Mar 18 when the temperature was below zero, my PWS reported correctly.
Without a history of when firmware was updated between Mar 2018 and now, and only spotty times when the temp dropped below zero trouble shooting is hard, but firmware is where the I am pointed. Was there a change in the way the temperature above and below zero is handled? Was there a change in the way Solar rad values are read/stored? Could there be a change in the way Solar data is stored on the thumb drive?
Is there a way to see older log information to see when firmware was updated/changed? Of course I have no local history before my USB failure in Aug 2018.
Re: Pressure is acting oddly
Posted: Tue Jan 15, 2019 8:45 pm
by Ag2000CO
The temperature dropped to 0°F again last night. This time I notice in the log that MB reports -- Bad th0(0) sensor data "temperature x10" (2097" out of range [-500:2000] --
Having installed two Temp/hum sensors (original and a new one from Davis) this is continuing to point to a processing/firmware error.

Re: Pressure is acting oddly
Posted: Sat Jan 19, 2019 9:26 pm
by Ag2000CO
Had temperatures below 0°F last night so had a opportunity to check firmware v3.9 (17 Jan 19 build 12694)
As illustrated below the temperature and Solar Radiation from my VP2 are not displayed correctly (The history reflects the same data). There was a near full moon last night, but it was not 700W/qm bright

Re: Pressure is acting oddly
Posted: Wed Jan 23, 2019 9:47 pm
by Ag2000CO
The odd pressure report that started this post has happened again. See the bump around 8:30-9:30am Jan 23.
Add to that the no temperature below 0°F and ~650W/qm of solar radiation as a floor. The log reflects only errors for the temp sensor
Re: Pressure is acting oddly
Posted: Fri Jan 25, 2019 9:45 am
by admin
Please read the neighboring thread about the below zero Fahrenheit problem.
Re: Pressure is acting oddly
Posted: Fri Jan 25, 2019 9:33 pm
by Ag2000CO
Meteobridge 3.9 (Jan 25, 2019 build 12697) loaded.
waiting for cold night, maybe tonight - this weekend.
thanks.
Re: Pressure is acting oddly
Posted: Sat Jan 26, 2019 8:42 am
by Ag2000CO
Log Messages as temp dropped to zero.

Re: Pressure is acting oddly
Posted: Sat Jan 26, 2019 8:02 pm
by Ag2000CO
The end of the log messages after ~10 hrs of Temp errors. Some of the messages in the middle are being overwritten in the log.

Re: Pressure is acting oddly
Posted: Sun Jan 27, 2019 6:41 am
by Ag2000CO
Meteobridge 3.9 (Jan 26 2019, build 12701), FW 1.4
Loaded, "Hopping for a cold night!"
Thanks Boris. Hope your vacation weather has improved.
Re: Pressure is acting oddly
Posted: Sun Jan 27, 2019 8:29 pm
by Ag2000CO
Boris you found the key. Temperature (AND READINGS) made it below zero °F last night.
When you get back from the sunny south, we need to take a look at the solar radiation.