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Not reading air pressure correctly

Posted: Sat 08 Feb 2014 11:02 am
by malc-c
last night I Cumulus reported an error in that it couldn't communicate with the base station. I tried the normal trick of trying different USB ports and still no joy. In the end I remove the batteries and fitted fresh ones. This resolved the issue and Cumulus began downloading data and everything seemed OK. OK I had a gap in the graphs, but I can live with that.

However today I noticed the pressure readings between the base unit and cumulus are different. My base unit is showing 965.3 m/b but cumulus is showing 999.4 Now given we are in the middle of a storm with a big low over the north of Ireland, I would tend to believe the base unit is reading correctly. If you look at the attached graph it gives the before and after readings when the unit failed to send data.

Can anyone advise on how to get Cumulus to record the values shown on the display. I've enclosed the diag folder entries if that's any help

Re: Not reading air pressure correctly

Posted: Sat 08 Feb 2014 12:05 pm
by steve
Cumulus is correctly displaying the relative (i.e. sea-level) pressure that your station is supplying:

08/02/2014 10:30:30.706 : EWUSB: Read pressure values: rel=999.8 abs=965.5 offset =34.3

So you need to set your console's relative pressure correctly (it's presumably lost its setting after the reset). See the FAQ: http://wiki.sandaysoft.com/a/FAQ#Cumulu ... et_console

Re: Not reading air pressure correctly

Posted: Sat 08 Feb 2014 1:01 pm
by malc-c
Cheers Steve, the console was set to abs rather than rel...