I have had a Hannah TDS meter for several years, but following the
discussions about the PWF, which said generally that the PWF had greater
accuracy, I bought a PWF. I have just completed a comparison of the readings
on the two on the CS I make. For the PWF readings I used the .57 conversion
multiplier which Ivan developed.
PWF TDS DIFFERENCE
17.10 16 1.1
11.11 10 1.1
15.67 14 1.67
dw 2.1 2 .1
` 15.38 14 1.38
dw 1.2 1 .2
In an effort to ensure accuracy, at this point I calibrated the PWF
13.90 15 1.1
dw 2.4 2 .4
14.36 15 .64
11.97 10 1.97
8.89 10 1.11
I think it was Ole Bob who pointed out that accurate readings with these
meters requires repeated tests with large quantities of liquid. For the small
quantities that most of us make, the readings are only approximate. If my
comparison is valid, since the difference between the readings is so small,
never reaching 2, is it worth investing in the higher-cost PWF?
George Allen
