TDS meter question. HELP right quick

[Guest]

hey i have an oakton TDSmeter and i am confused about the conversion factor with the meter and how it reads.

first. if the tds meter conversion is at .5 and the reading says 440ppm does that mean its really 220ppm ??

second. If this is all wrong what does my conversion factor need to be on?

thanks Fellow ICer's

BlowD

 

[Verite]

If your meter reads in ppm then it should be the face value. You should still verify it with a calibrated solution. I think the conversion comes in when making the comparission to EC @ 25c.

 

[Guest]

440 ppm @ 0.5 conversion factor means that electrical conductivity of you solution is 0.88 miliSiemen per centimetre. (0.88 mS/cm = 880 microSiemen/cm; 880 x 0.5 = 440 ppm).

 

[imnotcrazy]

^^^^You are correct sir

 

[Guest]

so does that mean at .5 factor and a reading of 440ppm means really 440 ppm... thanks dude

 

[Guest]

Sure, 440 ppm is just 440 ppm, with the same TDS-meter, though! Conversion factor is what mathematically connects EC and TDS. EC is direct physical measurement, TDS (ppm) is calculated, and since different manufacturers have different opinions on what the conversion factor should be for their meters, TDS readings may be very different for different meters, as much as 40% for the same exact solution!!!

 

[Guest]

You buy one PPM meter and you learn it with time.. you see what result it gives you and you can tell if that is ok, based on previous experiences...

That is what i'm doing

Peace and love,
Agnes

 

[AppleFarmer]

I had the same questions when I first bought my meter.
What solved it for mw was My nutrients...I use floranova and on the bottle is a measurement of ppm depending on dosage. I just mixed per the instructions and tested the water. It read pretty close to what the bottle predicted.
af

 

[JBLUNTS]

What is the correct ppm to be at?

 

[AppleFarmer]

JB I'm not sure of your question. Most nutrient companies give you a scale for ppm depending on dosage.
af