Forum >Replies by anonymous
Replies （15）
- Topic: getting more and more wetYou Reply: Hi,
Yes, things appear to have stabilised now.
You say I should water at 492? I had the watering point at 470 at one point, but that appeared to be far to dry.
torben - Topic: getting more and more wetYou Reply: Hi,
Yes, things appear to have stabilised now.
You say I should water at 492? I had the watering point at 470 at one point, but that appeared to be far to dry.
torben - Topic: getting more and more wetYou Reply: Hi,
Now back to 379.
torben - Topic: getting more and more wetYou Reply: Hi,
Now back to 379.
torben - Topic: getting more and more wetYou Reply: Hi,
I dont want to interrupt the sequence I have running for 2 sensors, but as far as I remember the reading in open air was 600+ and the reading in water was about 280. Should it be necessary to calibrate when I water the pot and then take the average of 10 readings as the wet base - and dont touch the sensor thereafter?
I now think that my wet basis setting of 362 is too wet and the setting of 382 for starting to water is far too low. I have to experiment some more.
torben
Hi,
I have just seen a drop from 378 to 364 over 8 minutes.
torben - Topic: getting more and more wetYou Reply: Hi,
I dont want to interrupt the sequence I have running for 2 sensors, but as far as I remember the reading in open air was 600+ and the reading in water was about 280. Should it be necessary to calibrate when I water the pot and then take the average of 10 readings as the wet base - and dont touch the sensor thereafter?
I now think that my wet basis setting of 362 is too wet and the setting of 382 for starting to water is far too low. I have to experiment some more.
torben
Hi,
I have just seen a drop from 378 to 364 over 8 minutes.
torben - Topic: getting more and more wetYou Reply: Hi,
I have about 10 potted plants watered automatically based on the sensor readings. Yesterday they started very wet. I took the average of 10 readings as a basis and found 362. The sensor is in one of the plants and it just sits there while I take readings and send them wirelessly every 8th minute to a computer. In the beginning the readings went from 362 to 367. Then they started going down to 357 and stayed there for quite a while and then started to crawl up again. Now they are at 363.
I started measuring in the afternoon with sunshine and continued through the night. Now it is morning the next day. The temperature went from about 20 C to 15 C.
At one time the reading went from 362 to 359 in one 8 minutes time interval.
I think the sensor will give another result if I take it up and put it down in a slightly different place. Because of that, and because the soil quality may be different from pot to pot, I find the basis as the average of 10 readings.
I suspect I should find the dry level to be around a reading of 385 to 405 which is surprising low.
The power supply is 3 x 1.5 V batteries. It started at 4.160 V and went rather quickly to 4.220 V where it stayed.
I hope that helps.
torben - Topic: getting more and more wetYou Reply: Hi,
I have about 10 potted plants watered automatically based on the sensor readings. Yesterday they started very wet. I took the average of 10 readings as a basis and found 362. The sensor is in one of the plants and it just sits there while I take readings and send them wirelessly every 8th minute to a computer. In the beginning the readings went from 362 to 367. Then they started going down to 357 and stayed there for quite a while and then started to crawl up again. Now they are at 363.
I started measuring in the afternoon with sunshine and continued through the night. Now it is morning the next day. The temperature went from about 20 C to 15 C.
At one time the reading went from 362 to 359 in one 8 minutes time interval.
I think the sensor will give another result if I take it up and put it down in a slightly different place. Because of that, and because the soil quality may be different from pot to pot, I find the basis as the average of 10 readings.
I suspect I should find the dry level to be around a reading of 385 to 405 which is surprising low.
The power supply is 3 x 1.5 V batteries. It started at 4.160 V and went rather quickly to 4.220 V where it stayed.
I hope that helps.
torben - Topic: getting more and more wetYou Reply: Hi I should add that up to the beginning (369) the values have been steadily increasing.
torben - Topic: getting more and more wetYou Reply: Hi I should add that up to the beginning (369) the values have been steadily increasing.
torben - Topic: getting more and more wetYou Reply: H,
I have the following set of readings from a capacitive soil moisture sensor V1.0:
369
362
359
357
No water has been added to the pot.
Can anyone explain?
best regards
torben - You Reply: Hi,
I feel a bit embarrassed - it is so simple.
The 4.5 V come from 3x1.5 V batteries (between Red and Ground) and the 0.170 V is what I measure (between Green and GND) no matter whether the sensor is in water or in air. What am I doing wrong?
best regards
-------------------
------- ---------------------------- Green
- - ---------------------------- Red
------- ---------------------------- GND
-------------------
I could not attach a pdf-file, nor a ong-file. I hope the above sketch will do.
best regards
torben - You Reply: Hi,
I did not use a computer. I simply connected the sensor to a 4.5 V power supply and then measured the voltage between the green wire end 0 V.
best regards
torben - You Reply: Hi,
I might add that I have coated the circuitry that is exposed with Urethan comformal coating.
I think I have seen the hanging of the sensor once before, and it is a serious problem (excessive watering) if it can happen.
best regards
torben - You Reply: Hi,
I have taken that into account. I establish a base reading as an average of 10 readings when the pgm starts up. In the case I am referring to I had left the sensor in place while taking readings and watering avery 15 minutes. In spite of the constant watering the reading stayed high - about 580 - ie. very dry. I only moved the sensor a couple of centimeters and the reading immediately changed drastiaclly towards wet - as it should. So, it is the hanging of the sensor that bothers me.
best regards
torben