Replacing a weather station

[Claire]

Hi,

Having got my set up running reasonably well, my weather station has just started to play up. The relative humidity readings over the past few days are getting lower and lower, it's currently about 45% which is obviously wrong, and I suspect that the electronics in the station have failed - it's a Fine Offset WH1080 and about 6yrs old. If I can't find a solution, I'm going off to Maplin / Clas Ohlson for a replacement.

What I want to know is the best way to set it up. If it turns out to be another Fine Offset type, can I just plug it in and carry on as normal or is there anything else I should consider?

Thanks
Claire

[Jim Easterbrook]

On 16/01/15 14:59, Claire wrote:
>
> Having got my set up running reasonably well, my weather station has
> just started to play up. The relative humidity readings over the past
> few days are getting lower and lower, it's currently about 45% which is
> obviously wrong, and I suspect that the electronics in the station have
> failed - it's a Fine Offset WH1080 and about 6yrs old. If I can't find a
> solution, I'm going off to Maplin / Clas Ohlson for a replacement.

One of my former colleagues replaced his humidity sensor. I expect you
can find instructions somewhere on the web (if you know how to use a
soldering iron).

> What I want to know is the best way to set it up. If it turns out to be
> another Fine Offset type, can I just plug it in and carry on as normal
> or is there anything else I should consider?

You can just plug it in and carry on, but you should delete the [clock]
and [data] sections from status.ini. Don't forget to stop pywws before
unplugging the old one and to edit status.ini before starting pywws
again after plugging in the new one.

You might want to consider using a 'user calibration' module to tweak
the new station's readings to match the old (or vice versa). One of the
example modules shows the sort of thing you can do. Remember to
reprocess any data affected by changes to your calibration module.
https://github.com/jim-easterbrook/pywws/blob/master/src/pywws/examples/modules/calib_jim.py
--
Jim Easterbrook <http://www.jim-easterbrook.me.uk/>

[Claire]

Hi Jim,

I've had look around the web for a replacement transmitter without much luck as this was my first thought as I'm always ken to repair if poss. I'm not afraid of a soldering iron but the time and cost involved would probably not be worth it in this case. I think an emergency shopping trip is in order tomorrow.

When deleting those sections in the status.ini file, do I remove them completely including the [clock] and [data] lines? Will these be recreated when I plug in the new station?

Also, being such a beginner, what commands/syntax do I use to stop and restart? Do I just stop pywws, unplug the usb, plug in the new station, then restart?

Thanks
Claire

[Jim Easterbrook]

On 16/01/15 18:41, Claire wrote:
>
> I've had look around the web for a replacement transmitter without
> much luck as this was my first thought as I'm always ken to repair if
> poss. I'm not afraid of a soldering iron but the time and cost
> involved would probably not be worth it in this case. I think an
> emergency shopping trip is in order tomorrow.

You'll then have spare wind & rain sensors which might be useful one day.

> When deleting those sections in the status.ini file, do I remove them
> completely including the [clock] and [data] lines? Will these be
> recreated when I plug in the new station?

Yes, delete the entire sections. Although they'll probably get recreated
anyway.

> Also, being such a beginner, what commands/syntax do I use to stop
> and restart? Do I just stop pywws, unplug the usb, plug in the new
> station, then restart?

If you're using an hourly (or more frequent) cron job, use 'crontab -e'
to comment out (put a # at the start of the line) the pywws task.

If you're running live logging, kill the pywws process ('ps ax | grep
pywws' will show you the process id).

Then unplug the old station, plug in the new, edit status.ini and
restart pywws / re-enable your cron job.

[Claire]

Hi Jim,

just thought I'd post an update in case it helps anyone else. I found a replacement transmitter at Maplin but it didn't work with my Clas Ohlson. What I have discovered is that the Clas Ohlson 1080 transmits at 868Mhz and the Maplin version is 433Mhz. I ended up buying a new one from Clas as it was half the price of the Maplin version. The good news is that I've got it working and my relative humidity increased to a sensible level. However I am still dubious about my readings. I've checked local Wunderground stations and my RH has dropped again. I am curious as to whether RH can vary over a small area as the other local readings are often quite different, and my closest station also has quite low RH results too. I'll continue monitoring and see how things go.

Claire