Cumulus Support

hi steve just been running c1 on windows 7 and noticed in the calibration some strange figures all the spike removal figure are 999.0 even the humidity one as a % never noticed this on vista

thanks

bruce

Bruce
My installation running on XP shows the same by default.

I have no calibration settings changed from original.

You have no values set to remove spikes from your data. Those are the normal default values.

The Cumulus help file says - "The "Spike removal" section allows you to specify the maximum differences between successive readings that you wish to allow, for Fine Offset and La Crosse stations. If a reading differs from the previous reading by the value you specify, or more, then it will be ignored. Be careful in your choice of values; if the difference is genuine, (i.e. not a 'spike') and exceeds your supplied value, then that reading will be 'stuck' at the previous value until a new reading returns to within your supplied difference.

Note that the spike removal values must be supplied in the 'native' units of the station, as shown on the screen. The gust value has no effect on La Crosse stations, as it only supplies one wind value - 'spike removal' is applied at the station level, unlike offsets and multipliers which are applied at a 'common' level; just use the 'wind speed' value."

So, I would guess that in the 48 seconds that a fine offset transmits new data, and the more frequent timing that Cumulus reads the data logger, that anything more than 10% to 20% change could be considered invalid data.

I see that the 'Spike Removal' fields are in the native units. What offsets/values have users been using to circumvent erroneous data.

I have discovered here that there is some device transmitting data on 433.9MHz with a strong signal (used a scanning receiver) which sometimes clashes with the data packet being sent from the transmitter to the console. (Now thinking of moving ) This I think may be causing some data corruption. So using the 'Spike removal' feature may help Cumulus to ignore this erroneous data.

Interested in any comments.

I was getting temperature spikes up to 2°C from an extended cable to the wind gauges, and I've settled on a 0.5°C temp spike maximum (highest legitimate change I've seen was 0.4°/min during a very sudden drop in temp over several minutes) and it's worked well for the last couple of months. Replacing the cable with CAT5e also helped. I no longer see any spike greater than 0.4° and then maybe only once a day on average.
Had no spikes in wind, humidity or pressure so haven't bothered to amend the default values.

The default values are just very large ones that will normally have no effect. It's just easier for me to do it that way than to have a separate setting to turn each one on and off.