well if it is hard coded for pressure then the station adjustment made by the OP should be to set his station to a known sea level pressure and subtract a correction for altitude (2.6 for 2300 ft I think) and all should then be ok
On Monday, 17 February 2020 07:09:35 UTC+2, ln77 wrote: > > Setting those that way won’t fix the problem. Those settings are hints to > weewx about what to use when the weather station hardware provides multiple > values. The WS28XX driver is hard-coded to interpret the data from the > station as weewx “pressure,” and that is the only pressure-related datum > sent by the WS28XX stations. > > -Les > > > > On 16 Feb 2020, at 17:09, Dan Blanchard <dan.z...@gmail.com <javascript:>> > wrote: > > Andrew, I've set barometer = hardware and altimeter = software and > pressure = software. I've restarted weewx, but nothing has changed in the > Loop. > > On Friday, February 14, 2020 at 9:30:06 PM UTC-8, Andrew Milner wrote: >> >> if indeed, and i now tend to agree, the station displays and outputs a >> manually adjusted barometer which is set to a sea level reading from local >> weather stations and not pressure then barometer should be set to hardware >> and pressure and altimeter set to software, and not as i previously >> suggested. >> >> On Saturday, 15 February 2020 06:22:07 UTC+2, ln77 wrote: >>> >>> OK… The “pressure” that your station is displaying is what it should be >>> displaying: the ambient air pressure, correct for your altitude. In weewx, >>> this is called “barometer” because that is what weather stations report for >>> barometric pressure. “Altimeter” is basically the same thing; there are >>> differences in exactly how it is corrected, but those differences are minor >>> and can be ignored for now. The distinction between what weewx calls >>> “barometer” and “pressure” is important, though, for anyone more than a few >>> hundred feet above sea level. >>> >>> From the manual, it appears that the WS-2813 uses a simple method for >>> correcting to sea level, by allowing the user to adjust a correction factor >>> that is applied to the actual measured pressure until the reading matches >>> some local reference barometric pressure report. This automatically also >>> corrects for any errors in the pressure sensor itself, a handy bonus. >>> There’s not reference in the manual to any other kind of pressure being >>> reported, so it only makes sense that what it transmits via the USB >>> interface is also this corrected pressure, i.e., “barometer.” But the >>> WS28XX driver documentation, and as far as I can tell the code also, assume >>> that the pressure reading fro the hardware is what weewx calls “pressure,” >>> that is, the actual ambient pressure before correction for altitude. As >>> far as I can tell, all of the WS28XX LaCrosse stations work the same way as >>> yours and actually send the corrected barometer reading. Maybe because the >>> LaCrosse documentation calls it “pressure,” it was mistakenly interpreted >>> as raw pressure reading in the driver. >>> >>> The bottom line is, I’m pretty sure the issue is that the driver is >>> wrong. I’m not familiar enough with that part of the weewx code to offer a >>> fix, but it should be pretty simple for someone who is familiar with that >>> code. >>> >>> -Les >>> >>> >>> >>> On 14 Feb 2020, at 19:44, Dan Blanchard <dan.z...@gmail.com> wrote: >>> >>> It is likely that I am mis-using the terms altimeter, barometer, and >>> pressure. I'll clarify what I mean here. >>> >>> What I previously defined as 'correct' pressure is that the pressure >>> reported by my station (LaCrosse WS-2813U-IT) matches the National Weather >>> Service barometer reading ( >>> https://forecast.weather.gov/MapClick.php?lat=47.715130000000045&lon=-116.94667999999996#.XkdkXDFKiUk). >>> >>> For example, *right now* my station is reading 30.06 pressure and the >>> NWS site is reporting 30.0 barometer. Ultimately I just want my WS-2813 >>> pressure reading to match the WU pressure reading ( >>> https://www.wunderground.com/dashboard/pws/KIDPOSTF43). Right now it >>> appears that WU is reading the weewx barometer reading. Is there a way to >>> have weewx report the pressure reading to WU? >>> >>> My WS-2813 outputs the manually adjusted pressure in the Loop records >>> (see attachment). I don't see a way to change that. Here is a link to the >>> manual ( >>> https://www.lacrossetechnology.com/media/catalog/product/w/s/ws-2813u-it.pdf >>> ). >>> >>> On Friday, February 14, 2020 at 9:22:17 AM UTC-8, Andrew Milner wrote: >>>> >>>> I would expect you to be reporting barometer = sea level pressure which >>>> is pressure adjusted for temperature and altitude because weather stations >>>> always report sea level pressures. >>>> >>>> Is what you call 'correct' pressure the raw pressure of the instrument >>>> or a pressure which you have set. Does the station output the raw >>>> pressure >>>> or the manually adjusted pressure in the loop records? >>>> >>>> >>>> >>>> On Friday, 14 February 2020 18:07:15 UTC+2, Dan Blanchard wrote: >>>>> >>>>> Andrew, that's a good questions; let me clarify. >>>>> >>>>> This issue started when Weather Underground (WU) stopped showing my >>>>> station on the maps. I found out that was because I was reporting an >>>>> incorrect barometric 'pressure.' As I dug into the details I found that >>>>> my >>>>> *station *was displaying the correct pressure (29.xx) but by the >>>>> time it got to WU, it was displaying the barometer reading (32.xx) from >>>>> weewx. This can also be demonstrated by looking at the data displayed at >>>>> /var/www/html/weewx/index.html (see attachment) so I assume that >>>>> weewx is taking the pressure from my station and somehow converting it or >>>>> exchanging it for barometric pressure before it gets uploaded to WU. I >>>>> just want the pressure from my unit to be what is reported to WU. >>>>> >>>>> Side note: I've been running this station for many years on a Windows >>>>> based system and it has been working fine. So I know the hardware side >>>>> is >>>>> working; just something different about how weewx reports pressure (or >>>>> barometer, or altimiter). >>>>> >>>>> Does that help clarify my issue? >>>>> >>>>> On Friday, February 14, 2020 at 2:24:31 AM UTC-8, Andrew Milner wrote: >>>>>> >>>>>> I am not sure I understand what you think is wrong with the readings >>>>>> of >>>>>> Pressure 29.89 >>>>>> Barometer 32.609 >>>>>> Altimeter 32.40 >>>>>> and why you believe something is wrong >>>>>> >>>>>> >>>>>> On Friday, 14 February 2020 05:57:36 UTC+2, Dan Blanchard wrote: >>>>>>> >>>>>>> Altitude is 2,320 ft. and the values are in the screen shot on the >>>>>>> previous post. Did you see that? >>>>>>> >>>>>>> On Thursday, February 13, 2020 at 7:16:11 PM UTC-8, Andrew Milner >>>>>>> wrote: >>>>>>>> >>>>>>>> I give up - looks correct to me. >>>>>>>> >>>>>>>> have you run from the command line and seen the LOOP and REC data >>>>>>>> weewx is receiving? >>>>>>>> >>>>>>>> what altitude is your station, and what values are you currently >>>>>>>> getting for pressure, barometer and altimeter? >>>>>>>> >>>>>>>> On Thursday, 13 February 2020 22:10:08 UTC+2, Dan Blanchard wrote: >>>>>>>>> >>>>>>>>> I don't know, but that makes sense so I did it. I'm still not >>>>>>>>> getting desired results though. >>>>>>>>> >>>>>>>>> On Thursday, February 13, 2020 at 9:38:55 AM UTC-8, Kevin Davis >>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>> Do you need a space between your minus sign and the adjustment >>>>>>>>>> value? >>>>>>>>>> >>>>>>>>>> On Thu, Feb 13, 2020 at 9:32 AM Dan Blanchard <dan.z...@gmail.com> >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> Hey Andrew, will you please look at the attached screen shots >>>>>>>>>>> and let me know if this looks correct? >>>>>>>>>>> >>>>>>>>>>> Do I need to restart (sudo /etc/init.d/weewx restart) after I >>>>>>>>>>> make these changes? I have and the changes don't seem to be taking >>>>>>>>>>> effect. Is there something else I need to do? >>>>>>>>>>> >>>>>>>>>>> With regard to the barometer and altimeter having the same >>>>>>>>>>> settings; I have probably misled. They are not exactly the same >>>>>>>>>>> but they >>>>>>>>>>> were relatively close to each other compared to the pressure value. >>>>>>>>>>> Here >>>>>>>>>>> are the current readings as of now when I run sudo weewxd >>>>>>>>>>> /etc/weewx/weewx.conf. >>>>>>>>>>> >>>>>>>>>>> pressure: 29.98 >>>>>>>>>>> altimeter: 32.57 >>>>>>>>>>> barometer: 32.74 >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Thursday, February 13, 2020 at 12:07:50 AM UTC-8, Andrew >>>>>>>>>>> Milner wrote: >>>>>>>>>>>> >>>>>>>>>>>> If you have a LaCrosse WS28xx station then according to the >>>>>>>>>>>> hardware guide the station outputs PRESSURE in weewx terminology - >>>>>>>>>>>> regardless of what LaCrosse call it - and weewx should calculate >>>>>>>>>>>> barometer >>>>>>>>>>>> and altimeter settings. >>>>>>>>>>>> >>>>>>>>>>>> If pressure is incorrect then it can be adjusted as you >>>>>>>>>>>> specified - by adjusting pressure (not barometer or altimeter) >>>>>>>>>>>> >>>>>>>>>>>> Make sure pressure is set to use hardware and barometer and >>>>>>>>>>>> altimeter are set to use software. >>>>>>>>>>>> >>>>>>>>>>>> I am surprised barometer and altimeter are the same values - >>>>>>>>>>>> have you set the station's altitude in weewx.conf, and have you >>>>>>>>>>>> specified >>>>>>>>>>>> software generation for the values? >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Thursday, 13 February 2020 09:23:27 UTC+2, Dan Blanchard >>>>>>>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> Andrew, are you suggesting that I make a 'correction' entry >>>>>>>>>>>>> under [StdCalibrate] such as barometer = barometer -2.8 assuming >>>>>>>>>>>>> that I am >>>>>>>>>>>>> getting a pressure reading of 30.13 and Barometer and ALtitude >>>>>>>>>>>>> readings of >>>>>>>>>>>>> 32.93? >>>>>>>>>>>>> >>>>>>>>>>>>> (see attached screenshot) >>>>>>>>>>>>> >>>>>>>>>>>>> On Wednesday, February 12, 2020 at 7:42:08 PM UTC-8, Andrew >>>>>>>>>>>>> Milner wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1. use stdcalibrate section of weewx.conf >>>>>>>>>>>>>> http://weewx.com/docs/usersguide.htm#StdCalibrate >>>>>>>>>>>>>> 2. FO station = Fine Offset weather station >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Wednesday, 12 February 2020 22:15:48 UTC+2, Dan Blanchard >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Andrew, how do I calibrate the pressure in weewx? Also, >>>>>>>>>>>>>>> what's a FO station? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Tuesday, February 11, 2020 at 8:01:08 PM UTC-8, Andrew >>>>>>>>>>>>>>> Milner wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> check that the absolute pressure is correct - I have had a >>>>>>>>>>>>>>>> FO station which had a dodgy pressure sensor before now. >>>>>>>>>>>>>>>> Calibrating >>>>>>>>>>>>>>>> pressure in weewx solved it. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> You received this message because you are subscribed to the >>>>>>>>>>> Google Groups "weewx-user" group. >>>>>>>>>>> To unsubscribe from this group and stop receiving emails from >>>>>>>>>>> it, send an email to weewx...@googlegroups.com. >>>>>>>>>>> To view this discussion on the web visit >>>>>>>>>>> https://groups.google.com/d/msgid/weewx-user/08c79655-b1af-4134-9a2b-82a4f52f051f%40googlegroups.com >>>>>>>>>>> >>>>>>>>>>> <https://groups.google.com/d/msgid/weewx-user/08c79655-b1af-4134-9a2b-82a4f52f051f%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>>>>>> . >>>>>>>>>>> >>>>>>>>>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "weewx-user" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to weewx...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/weewx-user/a24bec68-9459-43f4-8765-933c0c1f2490%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/weewx-user/a24bec68-9459-43f4-8765-933c0c1f2490%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >>> >>> > -- > You received this message because you are subscribed to the Google Groups > "weewx-user" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to weewx...@googlegroups.com <javascript:>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/weewx-user/4674c533-01b2-48fa-bb3f-707a6e24dd29%40googlegroups.com > > <https://groups.google.com/d/msgid/weewx-user/4674c533-01b2-48fa-bb3f-707a6e24dd29%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > > -- You received this message because you are subscribed to the Google Groups "weewx-user" group. 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