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Miscellaneous Debris => Tech Corner => Topic started by: kmahler on April 15, 2017, 10:48:34 PM

Title: Chart comparing two VP2's one with SHT31 and the other with SHT11 DFARS
Post by: kmahler on April 15, 2017, 10:48:34 PM

I currently have two VP2's mounted at the same height AGL and within two feet of each other. The first is a VP2 that has been upgraded to the SHT31. The second is a VP2 with the original SHT11 but also fitted with DFARS. Below are a couple of graphs showing the two units over a period of 22.5 hours, midnight to 10:30pm one spring day in Virginia. More specifically, April 15th, 2017. The first chart shows the readings from each station. The second chart shows the delta in higher resolution over the same time period.

I should add that the delta chart is shown in degrees Fahrenheit as I am an American and cannot think in Celsius.

I make no conclusions from these charts, I'm just sharing them for others who share my curiosity.

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Title: Re: Chart comparing two VP2's one with SHT31 and the other with SHT11 DFARS
Post by: Old Tele man on April 15, 2017, 11:05:42 PM

Pardon the punny expression, but looks "...NIGHT and DAY..." to me.

Title: Re: Chart comparing two VP2's one with SHT31 and the other with SHT11 DFARS
Post by: kmahler on April 15, 2017, 11:09:10 PM

Here are similar plots for the Bar Pressure between the two.

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Title: Re: Chart comparing two VP2's one with SHT31 and the other with SHT11 DFARS
Post by: kmahler on April 15, 2017, 11:09:49 PM

Quote from: Old Tele man on April 15, 2017, 11:05:42 PM

Pardon the punny expression, but looks "...NIGHT and DAY..." to me.

Well played!

Title: Re: Chart comparing two VP2's one with SHT31 and the other with SHT11 DFARS
Post by: mmorris on April 16, 2017, 11:38:34 AM

So you need to tell me what the Bar has to do with the temp sensor. As the Bar is taken from the console. And if someone slams a door in the house it can change that reading. For what it worth if I cal my Bar it is mostly off in a few hour that is the way it been ever since Davis has had a console with the Bar in it. (weather Monitor II) I still have one sets on the end table just reads inside temp inside hum and Bar.. I just can't believe Davis cal every sensor as they probably take a sensor from a box of sensor and stick it on the board. I've never had a console apart but I just can't see some assembler hooking every sensor and waiting for everything to stabilize and adjusting some pots.

Title: Re: Chart comparing two VP2's one with SHT31 and the other with SHT11 DFARS
Post by: kmahler on April 16, 2017, 07:36:05 PM

Quote from: mmorris on April 16, 2017, 11:38:34 AM

So you need to tell me what the Bar has to do with the temp sensor.

I made no such correlation between the two. I simply shared another graph showing the delta between two stations.

Title: Re: Chart comparing two VP2's one with SHT31 and the other with SHT11 DFARS
Post by: mmorris on April 16, 2017, 07:53:10 PM

OK. Carry on

Quote from: kmahler on April 16, 2017, 07:36:05 PM

Quote from: mmorris on April 16, 2017, 11:38:34 AM

So you need to tell me what the Bar has to do with the temp sensor.

I made no such correlation between the two. I simply shared another graph showing the delta between two stations.