Hi,

Welcome to WeeWX. Let's see if we can sort your issues out. First up the 
five minute update v poll interval. What you are seeing is normal 
operation. The poll interval is how often the GW1000 driver polls your 
GW1000 for data, in your case it's every 60 seconds. The driver takes this 
data and creates what we call a loop packet. WeeWX accumulates these loop 
packets and at regular periods WeeWX synthesises what we call an archive 
record. In your case it sounds like your archive period is set to 300 
seconds (five minutes). WeeWX saves this archive record to database and 
reports are then generated based on this and previous archive records in 
the database. 

At the risk of throwing you in the deep end you might find it worthwhile 
reading the Introduction section 
<http://weewx.com/docs/customizing.htm#introduction> of the Customization 
Guide <http://weewx.com/docs/customizing.htm>, which includes the section 
on LOOP packets vs archive records 
<http://weewx.com/docs/customizing.htm#LOOP_packets_vs._archive_records>.

Now for Metric units. You will see observations appear in various units 
throughout WeeWX. You might see units returned by the station when polled 
by the driver, you have the units emitted in the loop packets from the 
driver. You have the units in the archive record emitted by WeeWX, the 
units used in the WeeWX database and then the units used in any report 
generated by WeeWX. There are other places as well but these are the main 
ones. A given observation may appear in different units at one of these 
places compared to another, for example, your station may emit temperature 
in C but your database may store temperature in F and you may chose to 
display temperature in C in a report. At the end of the day the only thing 
that matters is that the units in any reports are what you want to see and 
that the values are correct.

One point of terminology, different observations use different units, for 
example temperature in C, humidity in %. Some of those observations will 
multiple different units that could be used, for example pressure in hPa, 
inHg, mbar, kPa. WeeWX uses what are called unit systems, with a unit 
system being a group of units that are used to cover all observation types 
supported by WeeWX. WeeWX uses three unit systems; US, Metric and MetricWX. 
Loop packets and archive records must follow one of these units systems. 
You will find further info on units in the Units section 
<http://weewx.com/docs/customizing.htm#Units> of the Customization Guide. 
Details of the units used in each of the three unit systems in at the Units 
appendix <http://weewx.com/docs/customizing.htm#units> to the Customization 
Guide.

As it happens the GW1000 emits observations using Metric values (not the 
WeeWX Metric unit system). So any temperatures, rain, pressures and wind 
speeds received by the driver from the GW1000 will be in Metric units. In 
the case of the GW1000 driver it emits loop packets in the WeeWX MetricWX 
unit system (usUnits = 17 is the giveaway). This is what your are seeing 
when your run the driver directly with --test-driver. The unit system used 
by a driver is really up to the developer, in the case of the GW1000 since 
all obs are Metric with rain is in mm and speeds in metres/second, the 
obvious choice is the MetricWX unit system. For the Davis stations most obs 
from the station are in US customary units so that is the unit system of 
the loop packets emitted by the vantage driver. Some drivers need to do 
conversion of various obs from one unit to another to fit in with the unit 
system of the loop packets being emitted by the driver. At the end of the 
day it does not matter as WeeWX takes care of unit conversions when and 
where necessary. Generally speaking, you cannot change the units emitted by 
the driver without modifying the driver code.

Again in your case I suspect that your database will use US customary units 
(if you were to look at your database you would find temperatures in F 
despite the GW1000 driver emittign temperatures in C). In the case of the 
GW1000 WeeWX takes care of converting the loop packet data from MetrixWX to 
US customary. Your archive records produced by WeeWX will use the MetricWX 
unit system but will be converted to US customary before being stored in 
your database.

Reports that are generated by WeeWX use a system of tags to populate the 
reports with data from the database and elsewhere. Where applicable these 
tags use a default unit that is specified in skin.conf or under [StdReport] 
in weewx.conf. Where applicable it is also possible to force a particular 
tag to use a given unit rather than the default. If you are a glutton for 
punishment you can read about tags and their use of units in the Tags 
section <http://weewx.com/docs/customizing.htm#Tags> of the Customization 
Guide.

The above has only scratched the surface regarding units, have a good read 
through and look at some of the links I have provided (they are better 
written than my words) and see if that gives you a clearer picture of what 
is going on and if that then answers your questions.

At the end of the day don't get wrapped about units, consistency and output 
is what matters.

Gary
On Thursday, 31 December 2020 at 14:49:22 UTC+10 James Litton wrote:

> My wife bought me an EcoWitt GW1001 Weather Station for Christmas.  I set 
> the unit up and have it reporting to Weather Underground and EcoWitt with 
> no problems. I want to be able to report to other sites as well so I did 
> some research and found WeeWX.  
>
> I have two issues that are tripping me up:
>
> (1) GW1000 Driver returns metric units.
>
> I set my WeeWX server up along with the GW1000 Driver 
> <https://github.com/gjr80/weewx-gw1000>. All seemed fine until I noticed 
> that my rainfall numbers were off.  After poking around, I noticed that the 
> output of PYTHONPATH=/usr/share/weewx python3 -m user.gw1000 --test-driver
>  shows my data (output below) in metric units instead of the expected 
> imperial units.
>
> 2020-12-30 22:03:12 CST (1609387392): UV: 0, dateTime: 1609387392, 
> dayRain: 54.6, daymaxwind: 4.6, inHumidity: 52, inTemp: 24.0, luminosity: 
> 0.0, monthRain: 54.6, outHumidity: 99, outTemp: 11.6, pressure: 1006.7, 
> rain: None, rainRate: 4.8, relbarometer: 1006.7, stormRain: 54.6, usUnits: 
> 17, uvradiation: 0.1, weekRain: 54.6, wh65_batt: 0, windDir: 1, windGust: 
> 0.0, windSpeed: 0.0, yearRain: 54.6
>
> Running sudo /etc/init.d/weewx status includes the following in its 
> output INFO user.gw1000: skipping rain measurement of 52.8: no last rain
>
> I've searched for fixes to this, but can't seem to zero in on a solution.  
> I think StdConvert may play a role here (mine is set to US), but I'm not 
> sure.
>
> (1) Local Apache data updates every five minutes despite poll interval 
> setting
>
> My poll_interval setting in my weewx.conf file is set to poll_interval = 
> 60 but for some reason my WeeWX reports are only updating every five 
> minutes. 
>
> Any suggestions for resolving this?
>
> Thanks
>
>

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