Unexplained VP2 pressure discrepancy

Davis Vantage Pro2, Pro1 (not firmware A)

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skyewright
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Unexplained VP2 pressure discrepancy

Post by skyewright »

The pressure that Meteohub is recording from my VP2 seems to consistently not to agree with the value on the console, i.e. Meteohub consistently records 0.4 mb less than the value shown on the console.

Other software that is simultaneously reading data from the same console[1] reports values exactly as shown on the console.

e.g
Console: 1017.1
WeatherLink: 1017.1
VPLive: 1017.1
Meteohub: 1016.7

There are no calibrations for this sensor on Meteohub's Settings page. Pressure is steady at the moment.

Any ideas?

[1] I use VirtualVP to allow this.
EmjayNet
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Re:Unexplained VP2 pressure discrepancy

Post by EmjayNet »

My VP2 is connected directly to the Slug but I see the same thing.

Console shows 1015.9 hpa
Meteohub shows 1015.5 hpa
wfpost
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Re:Unexplained VP2 pressure discrepancy

Post by wfpost »

same here with my VP2 and mh 4.5f
console 1022.2
mh 1021.8
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Re:Unexplained VP2 pressure discrepancy

Post by d_l »

Mine does the same also on version 4.5 with WeatherLink IP

meteohub 1014.4 mb

WeatherLink 29.967 inHg SL => 1014.799 mb SL

conversion factor: Pmb = 33.8639*PinHg
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admin
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Re:Unexplained VP2 pressure discrepancy

Post by admin »

looks like my formular misses some decimals...

double inhg2hpa (double x)
{
return (x * 33.85);
}

I will change conversion factor to 33.8639 with next update.

You can tweak actual readings by calibration time limited to the date, when you update the software.
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