TDS or Conductivity meter ?

[Sanjay]

Randy,

I was thinking of getting a TDS meter, but then I think I saw in one your posts you mentioned that a condcutivity meter can be used to measure the saturation of kalkwasser.

Can the same be done with a TDS meter ?

Is the conductivity meter a better general purpose choice as compared to the TDS meter.

Thanks

sanjay.

[Randy Holmes-Farley]

Electronic TDS, conductivity, and salinity meters are all conductivity meters that read in different units.

What you need to do is make sure that it covers the range that you are interested in. Not all of them cover then entire range.

For determining seawater salinity, that's about 53 mS/cm. For limewater saturation, that's about 10 mS/cm. For purity of RO/Di water, that's a few uS/cm. These are the units that a true conductivity meter will read in.

If it reads in some other units, you'll need to determine if the range is appropriate.

For example, I believe that the Pinpoint "conductivity" meter cannot read as high as seawater conductivity, and I believe that it's salinity meter isn't effective for measuring RO/DI water.

[LiquidShaneo]

Randy,

Do you have any recommendations on a good true conductivity meter? I'd like to be able to measure the conductivity for NSW, limewater, and if possible my RO/DI water. I have a feeling that measuring the conductivity of RO/DI water along w/ the other two is going to make the unit expensive. :) I'd be happy w/ NSW and limewater measuring ability tho. Can the PinPoint salinity meter measure limewater as well?

Shane

[Randy Holmes-Farley]

The ones that I use are quite pricey (hundreds of dollars). I don't off hand know of any good, low priced ones.

I don't know the ranges of the Pinpoints. Maybe someone else can tell us. You need about 9-10 mS/cm to measure limewater, and 53 mS to measure full strength seawater.