WH1080 rain sensor

[Repairman77]

Hi all,

Just wondering if anyone knows what happens to the rain gauge sensor when it stops working or reads less than half.
It started reading really low a couple of weeks ago and now has stopped altogether.

I dismantled it and checked for the normal things, spiders, seizures, etc. but nothing wrong there and the see-saw bucket assembly is moving freely. moving it up and down recorded nothing on the console.

I can only assume that there is something in the sensor unit next to the bucket assembly that has failed. The little magnet appears to be in the side of the bucket assembly and the cable is connected OK.

I don't really intend to spend any more money on it as I have a normal rain gauge in the garden and record it from there, and that's always a lot more accurate than the remote one.

Any ideas or is a failure of this part common? All the other sensors work fine.

Thanks,

Mike.

[mcrossley]

Check that the wires to the units are 'shorted' when the bucket is half way. The only things inside it are the tipping bucket, a magnet, and a reed switch. Either the plug/socket contacts are bad, the cable is fractured/disconnected (or the unit is corroded internally), the reed switch has gone bad, or the magnet has weakened.

[Repairman77]

Thanks Mark; likely to be the reed switch then as I've had problems with those before.

Will have it to bits again when I get some spare time and try and fix it.

Thanks,

Mike.

[Repairman77]

Well a modicum of success.

Removed rain box and checked it out on the bench. Re-soldered connections on the reed board just in case. Moving see-saw activated the reed OK and I checked continuity of lead, also OK.
Replaced the rain box and wired back the sensors on the roof after a squirt of Servisol10 on the contacts.

Got down the bottom where the console is and no reception from the transmitter.
Not sure why removing sensors would crash the transmitter?

After several attempts resetting the console by removing the batteries, popped up the ladder yet again and removed the batteries from the transmitter to reset it.

Back down the ladder and put the batteries in the console and after a minute it received the data.

Now have to wait till it rains. May have some storms tonight.
If that doesn't work I guess it's a fault in the transmitter unit.

This set-up is getting very close to the bin!!!

Had to have another console (under warranty) after a day's use because that packed up, and the whole lot is less than 2 years old; would have expected it to last a little longer even though it was pretty cheap; around £70 at the time.

If it doesn't rain I'll have to pop up there with a bottle of water to check it out.

Mike.

[Repairman77]

Success. Just had a shower and it's registered on the console.

I have a suspicion that resoldering the contacts on the reed board with a Weller TCP soldering iron (which works with an AC current to the heating element from an AC transformer) may have demagnetised the reed switch being in close proximity causing it to work again. May also work by bringing an old AC tape head demagnetiser near to it as well. Just a thought.

Now I need enough rain to recalibrate it against a proper rain gauge.

I also now need to know exactly which file to alter to get the data updated from my manual rain measurements over the past few weeks.

Anyone know what the lines to alter are?

Mike.

[steve]

Assuming it's the daily totals that you have, you need to edit dayfile.txt.

[Repairman77]

Thanks Steve, I take it I only need to edit the 15th item (Total Rain for the day). Max rain rate and max rain rate time shouldn't matter.
I assume the other monthly and yearly files take all their totals from the dayfile.txt.

Mike.

[Repairman77]

Update...
Corrected dayfile.txt and all appears to be working.
The calibration factor of 1.3 for Rainfall appears to be almost spot on for today. Rain gauge 8.1mm, 1080 remote rain box, and after correction factor applied in Cumulus, reads 8.2 (that's near enough for me).
Thanks for you help Mark and Steve.
Mike.

P.S. Anyone having problems with the rain box may be advised to demagnetise the reed; putting a mains soldering iron (plugged in of course) near to it should be enough to do the job. Unplug rain sensor first though.