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Jorginho:
Hi,

Sorry I wasn't clear about this....The old design means there was no cloud option back then as far as I know and if it was it was in its infancy. So since Davis never changed their basics a datalogger connected in a wireless way was the only way to go. Currently there are other options and Barani seems to chose from them, may be Davis would have done the same but the could not back then.

Indeed a VP3 might be completely different. Would be very sad.

johnd:

--- Quote from: Jorginho on September 02, 2020, 07:17:56 AM ---Currently there are other options
--- End quote ---

Which are other options are you thinking of? I've mentioned the current Davis technology and also ZigBee. And also LoRaWAN, SigFox (and probably NB-IoT as well) but these technologies do not seem to be suitable for real-time weather stations because they have such limited message bandwidth - fine if you need updates for a few parameters every 10-15 minutes, but not eg real-time wind or rain.


--- Quote ---Indeed a VP3 might be completely different. Would be very sad.
--- End quote ---

Sorry, I shouldn't have mentioned VP3! No sign of one happening at present.

Jorginho:
1) As compared to 2005..There are the options you mentioned nowadays.

2) They keep on building on the Vp2. I think that basic design was very good so it is pretty cheap not having to develop something very new for such a long time. Nothing has eclipsed these stations all things considered I feel.

At least in theory there is a gap that could be filled though by a competitor or nby Davis itself. I feel these things are nice to have and in some cases needed:
1) More accurate pluviometer, more hassle free. Higher accuracy and a better resiolution (0,1 mm).
2) A much better anemometer with 0,1 m/s resolution and lower startup speed
3) Better thermohygrosensor that reches 100% and has no wetbias (these things are reported)
4) Adding more thermometers without having to resort to 0,5 C resolution (or is this solved)?
5) cloud sensor/snowdepth sensor/lightningsensor/aurorosensor may be...?
6) Try to measure according to WMO standard at least when it comes to methodology (windspeed is the average over 3 seconds for instance, temperature is the 1 minute average of I think 5 intervalls of 12 seconds (or is it 12 intervals of 5 seconds)?

Things like that.

johnd:
@jorgino: Ah, you're talking about the VP2 design - I thought you were commenting on the wireless protocol. Also, I'm conscious that this is the Barani forum - we can talk about Davis in more detail elsewhere. But just to round out this particular topic:

First, and importantly, you always have to bear in mind station price; you can always have a higher specification for a higher price. A wireless VP2 in the US (with no sales tax, shipping or local support costs) is under $500 and in Europe with taxes etc maybe 700€. So that is the benchmark for the station itself. Add maybe $200/€ for data logging etc.

1. Rain gauge: The new VP2 tipping spoon seems well received and widely reported to have good accuracy. I'm not sure why you would want 0.1mm resolution. 0.2mm is an international standard and many locations have at least 50mm/month rainfall. So 1 tip is 0.4% of that rainfall. I think even if had 0.1mm that it would not register a 0.1mm rain shower because of funnel wetting.

2. Anemometer: The VP2 model is around ±0.5m/s resolution and starts up at around 1m/s. Again I'm not really sure in pure practical terms why you would want more. Most users are concerned with high wind speeds, not low wind speeds. And of course there is the Davis (LCJ) ultrasonic anemometer if you want a slightly better specification.

3. T/H sensor: Reports of the Davis SHT31 vary. Most users seem happy with it. If there were a way to get consistently better performance (100%) then I'm sure that it would be welcome. But show me another station in the $500-1000 range that reliably does offer better performance in a well-documented trial.

4. All Davis supplementary temp transmitters do transmit to 0.1°F resolution. The VP2 console can only receive to 1°F resolution but Weatherlink Live receives the full 0.1°F data. So that issue is effectively solved.

5. High quality sensors for cloud height, snow depth, visibility etc cannot be added to any station that I know of in this price range - the cost of good sensors is just too high. That said, there are eg depth sensors available in the Davis Enviromonitor range.

6. I think Davis broadly complies with WMO standards already for most measurements, eg the gust is every 2.5 secs or thereabouts (depending on wireless channel).

Not trying to make the case for or against Davis or Barani or anything else, but just setting out the baseline price/performance for a Davis station.

Jorginho:

--- Quote from: johnd on September 02, 2020, 12:29:39 PM ---@jorgino: Ah, you're talking about the VP2 design - I thought you were commenting on the wireless protocol. Also, I'm conscious that this is the Barani forum - we can talk about Davis in more detail elsewhere. But just to round out this particular topic:

First, and importantly, you always have to bear in mind station price; you can always have a higher specification for a higher price. A wireless VP2 in the US (with no sales tax, shipping or local support costs) is under $500 and in Europe with taxes etc maybe 700€. So that is the benchmark for the station itself. Add maybe $200/€ for data logging etc.

1. Rain gauge: The new VP2 tipping spoon seems well received and widely reported to have good accuracy. I'm not sure why you would want 0.1mm resolution. 0.2mm is an international standard and many locations have at least 50mm/month rainfall. So 1 tip is 0.4% of that rainfall. I think even if had 0.1mm that it would not register a 0.1mm rain shower because of funnel wetting.

2. Anemometer: The VP2 model is around ±0.5m/s resolution and starts up at around 1m/s. Again I'm not really sure in pure practical terms why you would want more. Most users are concerned with high wind speeds, not low wind speeds. And of course there is the Davis (LCJ) ultrasonic anemometer if you want a slightly better specification.

3. T/H sensor: Reports of the Davis SHT31 vary. Most users seem happy with it. If there were a way to get consistently better performance (100%) then I'm sure that it would be welcome. But show me another station in the $500-1000 range that reliably does offer better performance in a well-documented trial.

4. All Davis supplementary temp transmitters do transmit to 0.1°F resolution. The VP2 console can only receive to 1°F resolution but Weatherlink Live receives the full 0.1°F data. So that issue is effectively solved.

5. High quality sensors for cloud height, snow depth, visibility etc cannot be added to and station that I know of in this price range - the cost of good sensors is just too high. That said, there are eg depth sensors available in the Davis Enviromonitor range.

6. I think Davis broadly complies with WMO standards already for most measurements, eg the gust is every 2.5 secs or thereabouts (depending on wireless channel).

Not trying to make the case for or against Davis or Barani or anything else, but just setting out the baseline price/performance for a Davis station.

--- End quote ---

Haha...about this being the Barani side of the site: I was thinking of writing the same to you if you were to go in depth about Davis...Indeed this is the Barani side of the forum, but otoh barani seems to be reading this so may be he finds our tips useful...

1) new tipping spoon: I read inconsistent stories. One of my friends owns a Davis VP2 too and he did not note a lot of differences. The main problem seems to be when the winds pick up where the Hellmann pluvio reads much more than the Davis. If correct, the tipping spoon won't change it I guess. 0,1 mm is the Dutch standard. So than to me this would be nice. we get a lot more than 50 mm rain/month btw. The Barani btw gets you 0,1 mm if you want and is noted to be accurate.

2) I also have a Peet Bros 2100 (but no longer in use due to the wires....sadly). The aneometer is a lot more accurate and moves in breezes where Davis (not just one) is stuck. Barani iseems even better. Low windspeeds to me are very important because in cold winter nights with snow and bright sies the temp sometimes jumps. A little wind is a good reason why this is happened so when there is slight wind and I see the mercury is not moving down, I know why.

3) Good point. We have the SHt35 which I think which in theory is better. Other protocol so not suited for a Davis if i am correct. Again: here is where Barani may be does better but unsure.

4) I have no weatherlink live. I have a console and datalogger. Does the same thing apply? Thx!

5) Not cloud height, cloud cover. I have seen quite a few amateur designs which worked well. Not expensive but I can't say how this all would pan out. I am not saying that it should be professional quality. Davis has not professional quality. But good quality in line with what Davis delivers already.

6) no they don't. that is not according to WMO at all. WMO= 4 Hz for windspeed x 3 measurements/12. If I am correct. Temperature like I said. The thing is that a Peetbros 2100 ultimeter from 2009 in fact does measure according to those standards. Barani for sure does. And the Barani is in a comparable price range....

There are from at least soem angles better statiosn available so. If I could somehow get he barani working with Xbee/Zigbee or whatever and send the data directly to a receiver I would opt for it. May send the WMO data every minute or so. That would be fine. Not 10 minutes. Also  in this way they would not be hampered by the small bandwith Sigfox and others provide...I think that is why not all the data can be send to one account, but uyou need another one just for the windspeed.

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