Page 1 of 1

Loss of contact then Temp difference greater than specified

Posted: Fri 20 Jun 2014 8:59 am
by charles
Hi
I have a WH1080 that has worked fine for ages. I think the batteries are getting low as I have had a couple of loss contacts in the last couple of days but yesterday showed up another issue.

I have spike removal on temperature set to 2.8C which has worked well for me.

There was a loss of contact yesterday morning of three hours during which the temperature rose by nearly 6C. This meant that the spike removal came into operation for 8hrs until the temp came down to within the spike removal level.

So the question is:
Do I have to set the spike removal to a level to prevent this?
Or, could it be possible that on resuming contact on the first reading to ignore the spike removal setting?

diag file attached

Kind Regards
Charles

Re: Loss of contact then Temp difference greater than specif

Posted: Fri 20 Jun 2014 9:10 am
by steve
charles wrote:Do I have to set the spike removal to a level to prevent this?
Currently you would have to, yes. I know that some people do have relatively small values for spike removal, but it wasn't how I envisaged it being used. Fine Offset stations have a habit of producing very large sudden changes in readings, much higher than 2.8C, and it was those very large sudden changes that I had in mind when I added the (very simplistic) spike removal facility. But I do accept the argument that you wouldn't normally expect a change of 6C between successive readings, so a setting of 6C, which would have hit the same issue, wouldn't have been unreasonable.
Or, could it be possible that on resuming contact on the first reading to ignore the spike removal setting?
I do want to look at improving the 'false value' filtering at some point (even though there's a lot of code devoted to that already), and that suggestion is something I could consider. It would have to be done carefully, as 'sensor contact lost' is often associated with 'spikes'.

Re: Loss of contact then Temp difference greater than specif

Posted: Sat 21 Jun 2014 8:27 am
by charles
HI Steve,
Thanks for the speedy reply.
I think my first step is replace batteries. Then up the spike removal setting for now.

Spike removal was set that low as I had a period where temperature would jump by about 3c to 10c. Never did figure out what caused it!

Kind Regards
Charles