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  • September 4, 2018 at 8:13 pm #6013
    Wayne
    Participant

    I have finally received my A3 unit 820000E2 and it has been installed/running since late yesterday afternoon. Comparing the sensors I can compare with other commercial devices I already own it appears my A3 unit needs adjustment.

    The temperature appears to be 4 degrees higher than other commercial devices.
    The radiation appears to be higher than other urad units within 200km (not many units in my local area, so hard to determine if my unit is wrong)
    The pressure appears to the same as my other commercial devices
    The humidity is lower than my other commercial devices (it has been raining as I write this)

    uRADMonitor 820000E2
    type:8 hw:105 sw:135 SI29BG
    RAD:20CPM
    VOL:380V 21%
    T:18.79C
    P:100736Pa
    H:63.11RH
    VOC:556745
    N:38.17dB
    CH2O:0.00ppm
    PM2.5:3ug/m^3
    CO2:813ppm
    UP:43966s WDT:41s/400s

    IP:192.168.1.189
    SERVER:45.79.179.145
    INT:60s http:200 699/731

    September 5, 2018 at 1:01 am #6015
    henk harms
    Participant

    Hey Wayne,

    Henk here, I am just a few clicks down the road (Dayboro).

    I experience similar, the humidity, for example, is 20% off. Personally, I am not too worried about it at the moment and I write it off based upon the sensor locations.

    A question I have is your Formaldehyde working?

    Here is my dash
    https://www.uradmonitor.com/tools/dashboard-04/?open=820000E7

    LOL.. according to the uradmonitor site we are in China… I know China has bought half of Australia farming and agriculture land, but I believe it is still Australia, not China. (Then again with the day to day changes in Canberra we might be China by now… who knows).

    H

    September 5, 2018 at 9:23 pm #6025
    Wayne
    Participant

    Hey Henk,

    Yeah, Dayboro is just around the corner from me 😉 LOL

    I’d have to disagree with you on not worrying about the sensor accuracy. I would assume we all paid a decent amount of money for this product and would expect the sensors to be accurate and how is Radu going to achieve his goal if ALL the sensors are not within high tolerances of each other?

    No, my Formaldehyde is not working either 🙁

    I’m sure all these issues are just firmware bugs and Radu will release a firmware update to address these issues. But if the sensor is defective (Formaldehyde not working and inaccuracies), I’m sure Radu will do the right thing and replace the unit.

    Wayne

    Attachments:

    1. 20180904_214723916_iOS.jpg

    September 24, 2018 at 7:20 am #6057
    daniweb
    Participant

    Have a look of what I noticed

      Temperature, Humidity and CO2:

    The Oregon Scientific is at the same location of the A3, the KNX Siemens not exactly at the same position.
    For this measures I left the door and the windows closed to reduce the air moving influencing them.

    uRADMonitor A3: 25.6 °C, 55.17 %RH CO2 386.79 ppm
    Oregon Scientific: 21.8 °C, 64 %RH
    KNX Siemens AQR: 21.2 °C, 67.24 %RH CO2 562.88 ppm

    Regarding CO2 I can not tell who is better.
    For the temperature (maybe higher because inside of the case) and humidity (maybe due to the fun blowing air and higher temperature).

      Noise:

    When I measure for example with my mobile phone near the A3 31dB and 1meter from it I have max 23dB.
    And the noise may for sure be influenced by the fun…or ?

      VOC AIQ:

    Device 820000FA at 14:23 September the 4th of 2018.
    The VOC AIQ reports 348 and this is treated as severely polluted, this device is currently on my office at home (50cm from me).

    Now (10.09.2018 10:42) for the date time 14:23 September the 4th of 2018.
    The VOC AIQ reports something like 17 and not anymore 348??
    Hos is this calculated? all values at each request? When inserting the data?

    PS: most of this is coming from two entries in the community, but I have the impresison that the support is the best place and I have maybe better chance to get an “official” response.

    October 3, 2018 at 5:09 pm #6068
    uRADMonitor
    Keymaster

    Hi guys, sorry for the late reply, I’ve been travelling for most of September,

    Please use only the server values, visible on the dashboard or returned by the server API, as those are further compensated to correct issues related to internal heating that affects temperature and humidity readings.

    Although all units are calibrated against a common reference, there is a software interface in place that can be used to do additional adjustments where needed. We can apply this to any discrepancies in the returned parameters when compared to other equipment.

    Country for E7 and E2 is set to AU.

    For the 820000FA, please do a new test for Temperature and Humidity and let me know if you need any offset to be added. Again, make sure you are using the server returned results, not the local json. From you last post the correction would be T:-3.8 and H:+8.83
    The CO2 sensor has an autocalibration algorithm, that triggers every 24h. Most likely the readings will be correct.

    The VOC AQI algorithm has the purpose of providing comparable readings between the various MOX sensors used in the A3 units. It is very similar to the one developed by Bosch for their BME680 sensor. It uses the last 24hours of VOC raw readings to establish a minimum and a maximum, and then the readings are computed as a percentage scaled on the 0 to 500 interval. If you saw a big change it was due to a new 24hours interval introducing new min / max values to the calculations.

    October 4, 2018 at 7:28 am #6097
    daniweb
    Participant

    From you last post the correction would be T:-3.8 and H:+8.83

    Looking the humidity, now that we have less I have the impression that the difference is smaller, therefore I would point to a non linear correction.
    You know far better than me the sensor would it be possible that it is not linear?

    October 4, 2018 at 8:47 pm #6098
    uRADMonitor
    Keymaster

    The sensor used in the A3 is either the BME680 or the BME280 from Bosch. These are high spec sensors, I would expect very good linearity.

    October 5, 2018 at 9:24 am #6099
    Stratos Zolotas
    Participant

    What about the ozone, I’m on HW:106 SW:137 and I don’t get why ozone is mostly stuck on 50ppb, with only some down spikes and some very limited up spikes. Check the attached image. Sensor is 8200015E.

    Attachments:

    1. ozone.png

    October 5, 2018 at 9:33 am #6101
    daniweb
    Participant

    Hi, Why I do not have the Ozone measure on my A3 820000FA?

    October 5, 2018 at 9:35 am #6102
    daniweb
    Participant

    The sensor used in the A3 is either the BME680 or the BME280 from Bosch. These are high spec sensors, I would expect very good linearity.

    Maybe not the sensor, but the influence of the case and fun may be not linear depending of the temperature?

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