Pressure compensation

[ultralight]

Hi, I recently installed a Maplin N96FY weather station with Cumulus v1.9.2 and have noticed that the pressure showing on the base station is higher on the Cumulus read out on the PC, eg the base station reads 1006 and the PC screen reads 999.6. I have tried to update the readout on the PC page by using method as described on the Configuration page (correcting by the appropriate percentage) but the PC page remains unchanged. Any thoughts out-there?

[steve]

Cumulus only reads the 'offset' - the difference between the absolute (local) pressure and relative (compensated/sea-level) pressure - at start up, so once you set your station's relative pressure correctly, you need to restart Cumulus, or better, do it with Cumulus stopped. You shouldn't need to use a calibration setting in Cumulus, do any adjustment on the station itself.

[ultralight]

Hi Steve, thanks for your post, I have checked the the Base station pressure with another barometer and they both agree. Now how do I get the Cumulus page to read the same, am I missing something? Could you give me a step by step guide. The base station is at 15ft amsl.

[steve]

Cumulus will automatically display the same pressure as the station. Are you looking at the Relative pressure on the station? That's the value Cumulus displays. If you zip up the diags folder and attach it, I'll take a look.

[ultralight]

Steve, Thanks for the prompt reply, sorry to be a bit lost on this but could you explain 'If you zip up the diags folder and attach it'?

[steve]

See the post linked to near the top of the forum: 'Please click here before posting' for instructions.

[ultralight]

Hi Steve, after a nights sleep I got may head round it, thanks for your help. Did not realise that a re start was needed after entering the calabration info.