that caused a few problems too! 
I have thought of the batteries too, but I didn't want to do anything before Steve had a look at the diag-files. I thought the sensor unit only physically holds 2 batteries? Also you may not be aware that NiMH are possibly the worst choice for this application because they self discharge about 5% - 10% per week when sitting on the shelf, which is pretty much what this application is. They are a fantastic solution for high drain applications like digital cameras and GPS units, but very poor for low drain long charge holding applications like remote controls and weather station sensorsWestOz wrote:Hi folks
Mine was caused by a battery in my sensor failing. I use NiMH rechargeables and one of the four in the sensor is now completely dead and won't recharge. But as it was slowly failing the pressure reading was fluctuating wildly as you can see from the graph. Even after replacing the batteries it took almost an hour to steady.
Hi Charlie and GinaCharlie wrote:I thought the sensor unit only physically holds 2 batteries? Also you may not be aware that NiMH are possibly the worst choice for this application because they self discharge about 5% - 10% per week when sitting on the shelf, which is pretty much what this application is. They are a fantastic solution for high drain applications like digital cameras and GPS units, but very poor for low drain long charge holding applications like remote controls and weather station sensors
Ian, unless one has a weather station with a solar panel (such as is available with the Davis Instruments weather stations), I would strongly recommend that one uses good quality alkaline batteries (such as Duracell or Energizer or whichever brand is available in your country) in both the ISS (the external instrument sensor suite) and in the console (the internal sensor and display unit).WestOz wrote:My indoor sensor (non-solar, of course) on my Oregon WMR-918 has 4 x AAA batteries. Would you use NiCDs or Alkelines?
Thought I would try what you suggested as my error occured in Jul10 (not spanning two months). I have posted the old and new pressure graphs. It has worked a treat and all data is intact.werribee_au wrote:Hello Jens, I have been reading the following wiki entry thanks to Phil's thread suggestion.
http://wiki.sandaysoft.com/a/FAQ#Cumul ... et_console
I had a look at the diag files and noticed the following.
In cumulus.008 diag file the offset of -3.6
29-06-2010 20:12:55.578 : EWUSB: Read pressure values: rel=1001,5 abs=1005,1 offset =-3,6
Both cumulus.007 & .009 report an offset of 9.2
29-06-2010 15:02:14.265 : EWUSB: Read pressure values: rel=1013,4 abs=1004,2 offset =9,2
30-06-2010 10:43:57.157 : EWUSB: Read pressure values: rel=1015,7 abs=1006,5 offset =9,2
Your graph shows a drop at about 1930 but the diag file shows it set an offset of -3.6 at 2012, that I don't understand.
Ah, I think I have worked that one out. Cumulus was shut down at 1930. It started up at 2012, it read the console and set an offset of -3.6 (for some odd reason), downloaded data from the data logger and retrospectively applied the -3.6 offset and continued to use it until cumulus was shut down at 1040 and restarted at 1043. Then, the correct offset of 9.2 was set and used.
To correct the errors I'd probably reset the today.ini time stamp back to before 1930 on the 29th, edit out the data from that point forward in the Jun10log.txt,
Wait, I don't think this would be such a good idea without further instruction from Steve as we would be going from June to July here, there probably needs to be more files deleted or modified to do that. I'd wait for Steve.
But I would try adding the EWpressureoffset=9.2 entry to the cumulus.ini to prevent this from possible happening again.
Only my 2 bob's worth.