Author Topic: VP2 or...?  (Read 2008 times)

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Offline WxLover16

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Re: VP2 or...?
« Reply #25 on: July 13, 2017, 09:01:04 PM »
Supposedly humidity was at 22% around noon, which I also have trouble believing.
Certainly (your roof placement aside) one of the things that I've noticed about lesser sensors and PWS's (et al) is not their ability to read the temp fairly accurately, is their lack of doing it humidity wise. You may have trouble believing in your VP2... ;)

If I remember correctly, the specs are tighter for humidity than temperature across the spectrum with the 31. Let me know if that is not accurate.
Davis Wireless VP2 SHT31 24hr 24CFM FARS

Offline WxLover16

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Re: VP2 or...?
« Reply #26 on: July 13, 2017, 09:15:53 PM »
Supposedly humidity was at 22% around noon, which I also have trouble believing.
Certainly (your roof placement aside) one of the things that I've noticed about lesser sensors and PWS's (et al) is not their ability to read the temp fairly accurately, is their lack of doing it humidity wise. You may have trouble believing in your VP2... ;)

If I remember correctly, the specs are tighter for humidity than temperature across the spectrum with the 31. Let me know if that is not accurate.
Kinda apples to oranges, but for 99.99% of the population, the same linear response.

lol fair enough. Best sensor available to us to-date for sure, though.
Davis Wireless VP2 SHT31 24hr 24CFM FARS

Offline CW2274

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Re: VP2 or...?
« Reply #27 on: July 13, 2017, 09:17:00 PM »
Supposedly humidity was at 22% around noon, which I also have trouble believing.
Certainly (your roof placement aside) one of the things that I've noticed about lesser sensors and PWS's (et al) is not their ability to read the temp fairly accurately, is their lack of doing it humidity wise. You may have trouble believing in your VP2... ;)

If I remember correctly, the specs are tighter for humidity than temperature across the spectrum with the 31. Let me know if that is not accurate.
The temp could be better on the low end, but certainly better than anything previous.
Davis Wireless VP2 SHT31 24hr 67CFM FARS
RW Tipper w/ CoCoRaHS

Offline CW2274

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Re: VP2 or...?
« Reply #28 on: July 13, 2017, 09:17:36 PM »
Supposedly humidity was at 22% around noon, which I also have trouble believing.
Certainly (your roof placement aside) one of the things that I've noticed about lesser sensors and PWS's (et al) is not their ability to read the temp fairly accurately, is their lack of doing it humidity wise. You may have trouble believing in your VP2... ;)

If I remember correctly, the specs are tighter for humidity than temperature across the spectrum with the 31. Let me know if that is not accurate.
Kinda apples to oranges, but for 99.99% of the population, the same linear response.

lol fair enough. Best sensor available to us to-date for sure, though.
I removed the other post, it wasn't accurate.
Davis Wireless VP2 SHT31 24hr 67CFM FARS
RW Tipper w/ CoCoRaHS

Offline WxLover16

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Re: VP2 or...?
« Reply #29 on: July 13, 2017, 09:19:50 PM »
Supposedly humidity was at 22% around noon, which I also have trouble believing.
Certainly (your roof placement aside) one of the things that I've noticed about lesser sensors and PWS's (et al) is not their ability to read the temp fairly accurately, is their lack of doing it humidity wise. You may have trouble believing in your VP2... ;)

If I remember correctly, the specs are tighter for humidity than temperature across the spectrum with the 31. Let me know if that is not accurate.
Kinda apples to oranges, but for 99.99% of the population, the same linear response.

lol fair enough. Best sensor available to us to-date for sure, though.
I removed the other post, it wasn't accurate.

I was wondering where it went lol it's all good.
Davis Wireless VP2 SHT31 24hr 24CFM FARS

Offline WxLover16

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Re: VP2 or...?
« Reply #30 on: July 13, 2017, 09:21:30 PM »
Supposedly humidity was at 22% around noon, which I also have trouble believing.
Certainly (your roof placement aside) one of the things that I've noticed about lesser sensors and PWS's (et al) is not their ability to read the temp fairly accurately, is their lack of doing it humidity wise. You may have trouble believing in your VP2... ;)

If I remember correctly, the specs are tighter for humidity than temperature across the spectrum with the 31. Let me know if that is not accurate.
The temp could be better on the low end, but certainly better than anything previous.

Luckily I live in a climate that rarely gets below the mid teens in winter, so that won't be a problem down here.
Davis Wireless VP2 SHT31 24hr 24CFM FARS

Offline danb35

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Re: VP2 or...?
« Reply #31 on: July 15, 2017, 06:37:09 PM »
Well, it didn't come yesterday, but it did today.  Planted a fence post this morning, and installed the outdoor unit on it about a half hour ago.  As of now, my old station is reading 77F, 51% humidity; the VP2 is reading 77F and 85%.  Given the cloud cover and thunder going on right now, I'm pretty sure the higher humidity number is accurate.

Once the logger gets here, I'll start running my web site off the VP2.

Offline WxLover16

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Re: VP2 or...?
« Reply #32 on: July 16, 2017, 11:39:22 AM »
Well, it didn't come yesterday, but it did today.  Planted a fence post this morning, and installed the outdoor unit on it about a half hour ago.  As of now, my old station is reading 77F, 51% humidity; the VP2 is reading 77F and 85%.  Given the cloud cover and thunder going on right now, I'm pretty sure the higher humidity number is accurate.

Once the logger gets here, I'll start running my web site off the VP2.

Good deal, glad you got it setup. Most certainly the 85% is the correct number. Also, on sunny hot days with little wind, you will notice a big maybe more than 5 degree temp difference between your VP2 and old station. Aspiration and the triple walled core of the radiation shield goes a looong ways towards accuracy on those kind of days, plus your 31 (as has been said repeatedly) is the most accurate sensor to date. Enjoy the accuracy! I know I do!
Davis Wireless VP2 SHT31 24hr 24CFM FARS

Offline danb35

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Re: VP2 or...?
« Reply #33 on: July 31, 2017, 08:36:08 AM »
Logger arrived last week, took all of a minute or so to install.  Getting weewx reconfigured took a few more minutes, but it's been working well since then.  Temperature and humidity readings are looking much more realistic now.

Offline DaculaWeather

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Re: VP2 or...?
« Reply #34 on: September 28, 2017, 12:40:53 PM »
What he's getting at is when you have the 24 hr FARS with a 31, it will be as close to the ambient temperature as you can get (which means much cooler and much more accurate than your old station).
I understood that, but was trying for a little levity--which apparently didn't work too well.  Yes, I expect the readings to be a good bit cooler.
Just south of Savannah I see! That's where I was born! :-) Howdy from another Georgia native! :-)