Author Topic: Explore Scientific WSX 1001-Absolute and Relative offsets  (Read 1623 times)

0 Members and 1 Guest are viewing this topic.

Offline glf

  • Member
  • *
  • Posts: 3
Explore Scientific WSX 1001-Absolute and Relative offsets
« on: July 26, 2024, 11:30:16 PM »
Hi All,
Just purchased an Explore Scientific WSX1001 5 in 1 Weather Station (Bresser 5 in 1) and am having some difficulty configuring the Absolute and Relative offsets on the unit.
I realise the Explore Scientific WSX 1001 is not a fine offset weather station but would like to configure it as accurately as the unit will allow.

What l have done so far:-

* mounted/Configured the unit and connected it to both my wifi network and WeatherCloud.
* after speaking to the distributor of Explore Scientific, l was told the unit automatically configures the Elevation (not so sure about that given the Relative and Absolute readings and comparing them to nearby weather stations on WeatherCloud!).
* in the ‘Pro Weather Link’ Advanced configuration section, both the Absolute and Relative Offsets are listed as ‘0’
* the weather Station reports that the current Absolute pressure is 984 hPa and the Relative reading is 1008 hPa.
* referenced my elevation on www.freemaptools.com. It reported that my property in Castlemaine was 290m. (+2m to account for the height of the console).
* my nearest METAR weather station (Melbourne International Airport) reports 1016 hPa at sea level.

Thanks for your assistance in advance!

Regards,

glf

Offline gszlag

  • Forecaster
  • *****
  • Posts: 547
  • "barometers always need correcting"
    • Michael's Bay - Manitoulin Island weather
Re: Explore Scientific WSX 1001-Absolute and Relative offsets
« Reply #1 on: July 27, 2024, 06:38:51 AM »
Your barometer parameters appears to be similar to the FIne Offset system where elevation is set by calculating the theoretical difference in pressures between your barometer sensor elevation and sea level elevation. This difference is called the Relative offset. It is a fixed number. Your weather station's firmware likely just adds this Relative offset to whatever your current live Absolute value is showing.

The Absolute value is the raw pressure value that your sensor is reporting. It may or may not be accurate so if it needs adjusting for accuracy, you can enter an adjustment. This adjustment is referred to as the Absolute offset.

The whole idea, is to match your Relative value with the Altimeter or QNH value of a close-by airport. If after entering your Relative offset, your Relative value is not matching QNH, you need to adjust your Absolute offset(positive or negative number) until it does. Basically, we use the airport as a handy reference calibration tool to compare pressure values.

I would suggest reading our new barometer wiki for more information and examples of the calibration process:
http://meshka.eu/Ecowitt/dokuwiki/doku.php?id=barometer#barometer
Station elevation: 191 m
METAR: CYZE Elevation 189.9 m

Ambient Weather WS-2000
Ecowitt WS3900 console
Ecowitt GW1000/GW1100
Ecowitt WS68: Anemometer, solar radiation
Ecowitt WH40: Rain gauge
Ecowitt WH57 Lightning sensor
Ecowitt WH32E: Outside T & H sensor
Ecowitt WN30 temperature sensor
Stratus Rain Gauge (manual)
Starpath USB baro (barometer)
---
Raspberry Pi 5 4GB  WeeWX 5.x CMX 4.x
---
Barometer wiki: www.barometer-wiki.ca/barometer
---
Uploading to: AWN, ecowitt.net, Weather Underground, PWSweather.com, AWEKAS, Windy.com, WOW

Offline glf

  • Member
  • *
  • Posts: 3
Re: Explore Scientific WSX 1001-Absolute and Relative offsets
« Reply #2 on: July 27, 2024, 06:28:00 PM »
Thanks for your advice gszlag, much appreciated!!

The Wiki you referenced has certainly clarified what variables l need to change to ensure my Explore Scientific WSX 1001 is reporting accurate metrics on WeatherCloud.

The concern l still have relates to my distance from the nearest METAR weather station. Melbourne International Airport is 87km from Castlemaine and has very different geographical and climatic conditions!

Regards,
glf
« Last Edit: July 27, 2024, 06:31:19 PM by glf »


Offline glf

  • Member
  • *
  • Posts: 3
Re: Explore Scientific WSX 1001-Absolute and Relative offsets
« Reply #4 on: July 27, 2024, 10:59:04 PM »
Thanks for the recommendation Wooks61, have ordered one this afternoon.

Think this is the easiest and most accurate method of calculating the Absolute value on my Explore Scientific wsx1001 (given we are so far from the nearest METAR weather station)!

Looking at the Absolute value on the weather station this morning and comparing it to the values given on the online latitude/pressure calculator, it is really not that far out! However, l would like to configure it as accurately as possible.

Regards,
glf

 

anything