Topic: barameter lower then actual

[Zug]

I have a new 01301CCDI I just got, and I've noticed the barometer reads a fair bit lower then actual pressure. 

At this moment, actual is 29.9 (Environment Canada/local airport)  while the 01301 shows 29.34
My old Springfield agrees with the airport (mainly because it's adjusted that way)   I should mention I'm in a 8th floor apartment on a bit of a hill.

Will the learning mode correct this in time, or should I be doing the manual calibration on it to match it to actual pressure?  Sorry if this is a dum question, but I'm totally new to having a electronics weather station.

I'm also see it showing 99% humidity right now, even though the airport is 100%, and HEAVY fog right now, I literally can hardly see the building across the driveway right now.  is that normal?

thanks

[Beaudog]

Are you sure you are comparing like barometer readings.   Sea level to sea level and not se level to altimeter.   Most airports report altimeter.

The barometer is not correct until the at least the 14 day self calibration is done.

Read the specifications of the unit.   Humidity only goes to 99%  very few wx stations go higher than that.

[Zug]

yes, it's the public weather forecast I'm going by, http://weather.gc.ca/forecast/city_e.html?on-137&unit=i
guess I just miss read the self calibration stuff. the print in the manual is a bit small for my eyes these days..

So it's .5 difference right now, I'll see what it say the end of the month.

it never even occurred to me that the was a range limit on what it for report for humidity.  I guess they did it to save having another digit on the display..

[miraculon]

It might be interesting to see how well the auto calibration of the barometer works.
I took a quick glance at the manual for your station. On the "manual" mode, I wasn't sure if you just enter a barometric pressure from a nearby reference station, or you can enter altitude yourself. (if it is altitude, be sure to include the height of your 8th floor.)

From your comment, it sounds like it uses a matching method.

Will the learning mode correct this in time, or should I be doing the manual calibration on it to match it to actual pressure?  Sorry if this is a dum question, but I'm totally new to having a electronics weather station.

One word of caution if you do a manual calibration. Don't do it on a rapidly changing day, wait for a steady barometer reading in your area. The update rates on surrounding stations, and averaging algorithms make it very difficult to get a good match under rapidly falling or rising barometric pressure conditions.

Greg H.

[nincehelser]

The Acurite "learning period" starts with a reading of 29.92 inHg.  It may fluctuate greatly in the early days, and gradually settle down.

At about 2 weeks it should be "reasonable".  It keeps fine-tuning for a couple weeks after that.

How close it gets to the reading on your local weather report may vary.  I seem to have very good luck and get readings within a few hundredths of other reduction methods.  Others don't.

[Zug]

Unfortunately I was forced to reset the unit a few days ago, so starting the learning mode over again..  I'm temped to just manually set the barometer since I have a Springfeild mechanical barometer that I've had since I was a kid and is still dean on.  I may have missed something, but isn't the learning mode just averaging the reading again a generalized  average reading...?