Recent Posts

41

SoilWatch 10 / Re: Soil Specific Calibration

« Last post by aylashiv on April 09, 2020, 08:21:07 AM »

Please see attached calibration instructions together with a few handy tips about our SoilWatch 10 sensor.
The other attachment is the spreadsheet for easy calibration. Just enter your data points and get the calibration curve.

Soil-specific calibration for sandy clay soil below.

This calibration will fit most mineral soils quite well.

regards,
Piotr

Hi Piotr,

As you have mentioned the VWC meassured in a container, instead of this approach, we want to directly measure the VWC in the Soil near the active root zone of the plant, will this math can applicable with soil Watch 10? And for how much radius in the soil, this sensor is sensitivised to capture the readings.

Thanks,
Shiva.

42

SoilWatch 10 / Re: SoilWatch Life expectancy

« Last post by pinolec on March 09, 2020, 03:25:07 PM »

I have sent you another message this time from gmail account. Hopefully this time there will be no problem.

Kind regards,
Piotr

43

SoilWatch 10 / Re: SoilWatch Life expectancy

« Last post by [email protected] on March 06, 2020, 07:53:51 AM »

Hi Piotr,

Thanks,I have received your e-mail,but am unable to reply.
The mail keeps bouncing back.

Do you have any alternative mail address,if so can you please mail it to me,so I can give you a proper reply?

Kind Regards
Jacques

44

SoilWatch 10 / Re: SoilWatch Life expectancy

« Last post by pinolec on March 02, 2020, 09:43:37 AM »

Hi Jacques,

The 5.5V is too much as well. The 5.5V is the absolute maximum. Your goal should be to keep it within 3.1-5V
You can use 3.3V on the Arduino Mega board to power Soilwatch 10 sensor. Please make sure the remaining sensors you have are feed with specified voltage to avoid premature failure.
I will contact you via email to discuss the options.

Kind regards,
Piotr

45

SoilWatch 10 / Re: SoilWatch Life expectancy

« Last post by [email protected] on February 28, 2020, 09:54:35 AM »

Hi Piotr,

Sorry , I see that I made a mistake,I meant 5.5V.
I think I will tone it down to 5V and see how it goes.
The second unit has a different power module that gives out a regulated 5V also feeding the arduino via usb that has 2 x Soilwatch probes connected.
The one soilwatch is still working , but the other one failed after 3 months like the other unit supplying 5.5v.

I know when using the usb the regulator is bypassed, so maybe a spike is getting through and the other sensors are more tolerant.
I will tone down the voltage to 5V on this build and see how it goes and for future build go through the regulator just as an extra measure should my powersupply drop the baal and send a spike through.
Kind Regards
Jacques

46

SoilWatch 10 / Re: SoilWatch Life expectancy

« Last post by pinolec on February 25, 2020, 09:58:45 AM »

Hi Jacques,

Please clarify, do you feed 5.85V to the Mega 2650 via USB port?
Please note that USB specify voltage in the range of 4.40 - 5.25V.  So the 5.85V is outside of the standard voltage for USB and would be lethal for SoilWatch 10 sensor (5.5V absolute maximum).

Kind regards,
Piotr

47

SoilWatch 10 / Re: SoilWatch Life expectancy

« Last post by [email protected] on February 25, 2020, 06:36:09 AM »

Hi Piotr,

The unit that control the valves is on a separate system that runs on its own sbc.

The unit that the soilwatch is connected to consists of the following:

1 x Mega 2650 Original
2 x Soilwatch probes
2 x temp probes
1 x SD Card Modules
1 x BME Module
1 X RF Communication module.

The unit is places in n nut farm.

The entire system on peak pulls about 320mAh(Worst case senario) for 800ms
The power is supplied by Solar.
Solar panel is connected to voltage regulator that puts out constant 5.85v to usb connection(Same voltage as pc usb port) and also charges the battery.
The regulator(Charge board) is capable to supply 1 Amp max(Not that it is needed)
The system has been running since last year September , all hardware and probes exactly the same since then except for the soilwatch probes that is the second pair now

Thanks in advance.

Kind Regards
Jacques

48

SoilWatch 10 / Re: sometimes 6 percent difference in pure water

« Last post by pinolec on February 24, 2020, 03:01:07 PM »

To get decent repeatability out of ESP32 ADC use code below as the starting point. The capacitor is also a must.

Code: [Select]

/*  Analog read for ESP32
    To minimize the noise connect 100nF capacitor between ADC pin and GND as per https://docs.espressif.com/projects/esp-idf/en/latest/api-reference/peripherals/adc.html#minimizing-noise
    Code below multisample ADC on sensPin and average the results.
    The result is printed on Serial port
*/

const int sensPin = 34;
int sensValue = 0;


void setup() {
  Serial.begin(115200);
  delay(1000);
  analogReadResolution(10); //set ADC resolution to 10bits
}

void loop() {
  // Reading sensor value
  sensValue = AvgAnalogRead(sensPin, 1024); //Average 1024 reads to make good readings
  Serial.print((sensValue*3.3)/1024);//convert to Volts
  Serial.print("V ADC:");
  Serial.println(sensValue);
  delay(500);
}

int AvgAnalogRead(int adcToRead, int samples){

  long x=0;
  int i = samples;

  while(i){
    x+= analogRead(adcToRead);
    i--;
  }
  return (x/samples);
}


49

SoilWatch 10 / Re: SoilWatch Life expectancy

« Last post by pinolec on February 24, 2020, 07:59:52 AM »

Hi Jaques,

Thanks for the details about your setup.
You mention you that Arduino Mega control valves. Could you let me know what valve it is and how you have it connected to Arduino?
Have you had other devices/parts connected to the Arduino?
I assume you power the Arduino from mains. Is that correct?

Kind regards,
Piotr

50

SoilWatch 10 / Re: SoilWatch Life expectancy

« Last post by [email protected] on February 20, 2020, 09:05:27 AM »

Hi Piotr,

Thanks for the reply.
At this stage I would be happy with 2 years, I really like your soil senor and hope we can get the life span up.
I use it with an Arduino Mega 5v, It measures 4.99V on the pin.
Brown to vcc
White on Analog pin
Green on Ground.

The probe is being read every 10s during a scheduled time during the day to close valves.
I do not have a broken probe with me anymore , I will asked one of the customer to courier me the probe to do the testing you request and get back to you.

Kind Regards
Jacques