TDS calibration

[vinny]

How or where can I go to get my portable TDS meter calibrated. I just checked my DI water and it was all over the place from 8 to 150 it was non stop. I replace my color changing resin just three weeks ago and the color is still a solid blue. I then checked my RO water and the same happened 3 to 89. I replaced all the filters on my RO unit a few months ago.

[nunofs]

If it's jumping like that, the sensor is probably bad. If it was miscalibrated it'd give a wrong reading (high or low) but not jump around like that. You can try calibrating with distilled water (should read 0) just to be sure. There are also calibration solutions you can buy, or make your own.

[Jim Tansey]

Nunofs,

Nice to see you on the board!!! As for the TDS calibration the first thing I would do is change the batteries (been their done that).

Jim

[vinny]

Thanks Guys i'll do both :).

[xp964]

If that doesn't work, you can try cleaning the probe; EC/TDS probes can get a soot-like build up on them that will interfere with readings.
Graphite TDS probes usually have a slot right down the middle - try pulling a piece of moistend corregated cardboard through it. If that doesn't do it, next try a fine grit, wetted emery board. (With either method, it's important not to "saw", just pull it gently through once or twice.)

[vinny]

Well I finally got around to it changed the batteries it's working the right way again. I bought the batteries at Walmart 3 for $5.