Recent Posts

31

SoilWatch 10 / Re: Soil Specific Calibration

« Last post by pinolec on May 11, 2020, 10:04:21 AM »

Can you explain the all the formulas is your attachment and What "x" and "R" indicates.

Thanks,
Md Afroz Hussain.

The x is the sensor output in volts. The R² is the coefficient of determination. The closer the R² is to the 1 the better approximation it offers.

Kind regards,
Piotr

32

SoilWatch 10 / Re: Soil Specific Calibration

« Last post by pinolec on May 11, 2020, 09:52:46 AM »

It does not matter too much. I mean VWC is a way to measure humidity, probably the most correct measure. There are some other moisture sensor like Xiaomi Flora which provides humidity in percentage between 0 and 100, hence my question. If there was a direct translation or conversion in between VWC and humidity percentage on a 0 to 100 range. I have just ordered 8 sensors for my garden and have already prepared some ground prepared to make the calibration   

I assume you can map the output of the sensor to 0 - 100%
y = x/3*100
where x is in volts and y is the calculated output in % (ranges 0-100%)

This is not guaranteed to be accurate or comparable to Xiaomi sensor output or any other sensor. 

Kind regards,
Piotr

33

SoilWatch 10 / Re: Soil Specific Calibration

« Last post by Afroz on May 11, 2020, 09:01:22 AM »

Can you explain the all the formulas is your attachment and What "x" and "R" indicates.

Thanks,
Md Afroz Hussain.

34

SoilWatch 10 / Sensitivity of sensor

« Last post by Afroz on May 11, 2020, 08:25:05 AM »

Hello pino tech,

I am using soil watch 10 from last 1 year,want to know what is the sensitivity range of the soil watch 10.

Thanks,
Md Afroz Hussain.

35

SoilWatch 10 / Re: Soil Specific Calibration

« Last post by Barto64 on May 10, 2020, 05:38:40 PM »

It does not matter too much. I mean VWC is a way to measure humidity, probably the most correct measure. There are some other moisture sensor like Xiaomi Flora which provides humidity in percentage between 0 and 100, hence my question. If there was a direct translation or conversion in between VWC and humidity percentage on a 0 to 100 range. I have just ordered 8 sensors for my garden and have already prepared some ground prepared to make the calibration   

36

SoilWatch 10 / Re: Soil Specific Calibration

« Last post by pinolec on May 05, 2020, 08:34:33 AM »

When using one container and just adding more water may introduce a bigger error. This may accumulate and at the end of calibration may be significant. I assume when you are caution you may do the calibration using just one sample container.
For lawn, I would suggest installing the sensor as in the picture below.

The Volumetric Water Content [VWC] is shown as a percentage of water in the soil by volume. Please clarify what you mean by humidity percentage.

Kind regards,
Piotr

37

SoilWatch 10 / Re: Soil Specific Calibration

« Last post by Barto64 on May 04, 2020, 08:58:14 AM »

Excelent explanations, will go for that, I was a bit disappointed with the readings I was getting from the sensor. I am still doing my own research before ordering a bunch of sensors and have a few questions:

- Not a big deal, but why do I need 10 samples of the volume of the smaller container if I can add the additional water to increase the VWV to the same soil sample along the various iterations.

- Is the any specific position how the sensor should be placed under the grass ? In my case I want the sensors to ensure an adecuate watering of my lawn.

- How can I translate VWC to Humidity percentage ?

38

PIMM / Re: Plastic injection molding is safe

« Last post by pinolec on April 21, 2020, 12:03:51 PM »

Hi,

The short answer is no. Not up to the EU standards. 

1. The easiest way to make it safer is to add another pneumatic valve which will have to be operated to open the main supply to the machine. The goal is that both hands of the operator are on the controlling valves. There is no way to insert one hand between clamping plates and operate the clamping mechanism. This upgrade makes it much safer. But will not stop the 2nd person to put the hand where it can be crushed.

2. That's why the machine enclosure will protect better. Possible solutions include metal or plastic sheet. Chicken mesh wire may also be a good option. We need to leave the opening for mould insertion. The best option will be sliding door (transparent plastic sheet) with microswitch and solenoid valve. The valve should be closed when the door is open. This valve as with the 1st option should be placed before other valves.

The second option is the best option. Also electrically make sure every metal part of the machine has a good connection to the earth.

This is the basics which will make the machine pretty safe. Personal protection equipment should be used - good quality leather gloves should be used all the time.

Kind regards,
Piotr Trembecki

39

PIMM / Plastic injection molding is safe

« Last post by omarmohsen on April 20, 2020, 10:25:01 AM »

I was wondering if working with this injection molding machine is safe and what are the workarounds to make it safer?

40

SoilWatch 10 / Re: Soil Specific Calibration

« Last post by pinolec on April 15, 2020, 08:13:34 AM »

Dear Shiva,

This equation translates the readings of the sensor into VWC in most mineral soils. So yes, you can measure the VWC in the soil next to plants root.
The most significant influence on the sensor reading has the area within 1-2mm of the sensor. The sensor relay on good contact with the soil. So always make sure the sensor has good contact with the measured soil.

Kind regards,
Piotr