FOR SOIL CALCULATIONS USE THE TOP CALCULATOR FOR LIQUID SOLUTIONS / HYDROPONICS USE THE BOTTOM CALCULATOR
SOIL CALCULATOR
HYDROPONICS CALCULATOR / TESTING CALIBRATION 4.0 or 7.0 SOLUTION
IMPORTANT THINGS TO KNOW AND REMEMBER ABOUT THIS PROCESS:
- Your reading will be either + or – ( POSITIVE OR NEGATIVE ) on your digital multimeter
- The range can be from -400 to +400mV ( milli-Volts) PAY ATTENTION TO THE POLARITY IF IT IS NEGATIVE OR POSITIVE
- ————- HERE IS AN EXAMPLE OF A NEGATIVE READING —————–
- Keep the Positive Test Terminal and Negative Test Terminal 1inch to 3inches apart .. ” The closer together the higher the accuracy of THAT SPOT ” where-as further apart they are averaging soil PH and averaging. Do not have the leads any further apart than 3inches max. It is advised 2inches for typical readings.
- Most all digital multi-meter’s during manufacturing processes have to test read various loads and voltages during calibration thus this process shared should be consistent with most all DMM’s
- ** VERY IMPORTANT ** – When taking a reading the meter will hit either it’s maximum negative number or it’s maximum positive number. You’ll know this because it will slow down and seem like it’s just about to freeze at a particular number. This is your READ POINT meaning, that’s the number you write down because soon after you’ll notice the meter will begin dropping or rising in the opposite direction from that READ POINT. Example, seconds after you enter your DMM’s probe into the soil and take a reading say the readout climbs to 50.1 mV since there is no minus sign or – which indicates a negative reading this means your reading a positive number. If your READ POINT is 50.1 you’ll see the numbers climb from 1,2,3,4, 20,30,40…45,46 all the way up to the Read Point of 50.1 in this example and you’ll notice the meter doesn’t seem to go higher this indicates you have acquired the READ POINT. Then you’ll notice not but seconds later where it seemed to hold at 50.1 it will begin dropping back down .. this is NORMAL behavior … ignore the numbers as it drops down, the important number is getting the READ POINT. However, remember your meter could be reading into the negative range, and the same thing applies so let’s start again. You put your DMM probes in the soil , you see the numbers going from -1 to -2 to -3 and so on as it goes more and more negative and say it reads a -30.4 as in the video and it stays there for a 2seconds and doesn’t really change then your READ POINT is -30.4 write that down, because not but shortly after it will reverse and begin going from -30.4 to -29, -28 , -27 , -26 and so on ( to an untrained eye it appears erratic and to be bouncing around but the magic is that READ POINT ) !!!! So you will have to baby sit and pay attention during this process to the meter’s reading, but the calculator provided above is astonishingly accurate for a SOIL READING ..
- *** FOR HYDROPONICS *** – Use the ” BOTTOM ” Calculator if you are testing PH4.0 or 7.0 LIQUID SOLUTIONS or testing Hydroponics Resovoir PH levels, the bottom calculator has a different formula than the top calculator which is specifically made for soil PH tests.
