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Soil Moisture sensor

Discussion specific to Davis weather stations
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Mapantz
Posts: 1272
Joined: Sat 17 Dec 2011 11:55 am
Weather Station: Davis Vantage Pro2
Operating System: Windows 11 x64
Location: Dorset - UK
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Soil Moisture sensor

Post by Mapantz »

I've picked up a brand new soil moisture sensor for £20.

I don't know which cable goes where.. the wires are green, one wire has a white stripe. There's no information anywhere to tell you which wire is supposed to go in to..

Does anybody know?
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mcrossley
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Weather Station: Davis VP2/WLL
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Re: Soil Moisture sensor

Post by mcrossley »

I don't think it matters which way round the wires go.
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Mapantz
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Joined: Sat 17 Dec 2011 11:55 am
Weather Station: Davis Vantage Pro2
Operating System: Windows 11 x64
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Re: Soil Moisture sensor

Post by Mapantz »

Thanks Mar, thought as much!

Got it all working. I had a special stand fabricated to mount my station in a tidy manner. I painted it all up and concreted it in, then added pipework to route all of the cables.

https://postimg.cc/3ycM350y
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mcrossley
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Re: Soil Moisture sensor

Post by mcrossley »

£20 was a bit of a bargain! :o
Mapantz
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Joined: Sat 17 Dec 2011 11:55 am
Weather Station: Davis Vantage Pro2
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Re: Soil Moisture sensor

Post by Mapantz »

mcrossley wrote: Sun 23 Jan 2022 5:09 pm £20 was a bit of a bargain! :o
Yeah. A friend nearby had one he was going to use, but didn't realise that they come with bare wires. He didn't want to fork out for the transmitter, so he offered it to me for free. I couldn't accept it for free, so I paid £20 as a thank you. I probably wouldn't have bought one, but I couldn't resist for that price.

A weather station that I follow down in Plymouth has the full Davis set up. I noticed that they are sending soil moisture to the Met Office WoW site, but it is as a percentage.
Did you notice that offering when you added the soil temperatures?
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mcrossley
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Re: Soil Moisture sensor

Post by mcrossley »

They do accept soil moisture in percent, but there is no simple method to convert from soil moisture in cB to percent saturation, it depends on the soil type and appears to be non-linear.
I guess a linear function between something like 10 cB and say 70-100 cB would be an approximation.
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SJG1976
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Re: Soil Moisture sensor

Post by SJG1976 »

Think that's going to be my Next Purchase.

Soil Moisture Station.
But soooooo expensive and then having to add the sensors.

Leaf, soil, temp

I've currently got an EcoWitt on the go just for a cheap soil moisture sensor, that seems to read in % rather than cB

Probably wasted a bit of money going for the Ecowitt and should have just stuck to Davis...

.
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