The COM-100 is a conductivity meter [as all meters are] and is to be
used in CS as a conductivity meter and read in "uS" as this most closely
approximates the relationship of conductivity to ionic silver water.
But! Only after it has stabilized.
[I think] EIS/CS has free ions and anions that have not yet associated,
hence free and exposed electrons, when very fresh and shows as more
conductive than after it has stabilized.
"Stabilized" EIS/CS [LVDC generator] samples were measured for
conductivity after 8 days and those samples were sent to be tested by an AA
Spectrophotometer for "true" total PPM
At 7 to 12 PPM with 85-87% being ionic, the ratio was very close to one
to one, measured by uS meter at 70 deg F
Meters don't read anything BUT the ionic part.
Every 10 degrees of temperature over 70 will add about 3 uS to the meter
reading.
The relationships may be different when checking LVAC EIS [To be
determined sometime in the future]
Conductivity [uS] is conductivity and it should read the same in all scales.
PPM is "derived" from conductivity run through a mathematical formula to
approximate PPM.
No meter "actually" measures PPM.
Since various dissolved solids have different conductive properties due
to different numbers of electrons, three scales are most commonly used in
the water industry depending on what mineral salt is suspected of being
dominant in the water sample.
Most "PPM" meters that don't offer a choice run the NaCl scale.
* 442" Natural water - this standard solution was developed by the
Myron L Company to simulate the properties of natural water (rivers, lakes,
wells, etc.). The acronym 442 represents (4) 40% Sodium Bicarbonate, (4)
40% Sodium Sulfate, (2) 20% Sodium Chloride. The 442 standard is the best
choice to use when measuring water samples such as city water, rivers,
lakes, and wells.
* NaCl - this standard solution is made of Sodium Chloride and is to be
used to calibrate an instrument that measures solutions such as seawater
and brackish water where predominate ions are NaCl (sodium chloride).
* KCI Standard - this standard solution is made from Potassium Chloride
and is an international standard to calibrate instruments that measure
conductivity. [uS] The unit of measure for KCl is micromhos/microsiemens
or millimhos/millisiemens.
1.3 uS water isn't wonderful.
Apparently, from your description, it's OK this time.
Depending on "what" is in the water, it should be "OK" and I've had good
results even at 5 uS. [And some iiffyness at .5 uS]
Just a touch of the 'wrong' stuff can mess you up.
"Good" water should read between .2 and .8 uS.
Even then "what" vs "how much" can be a problem when nit picking EIS /CS
quality.
There's no way to tell "what" is in the water, so, if a problem crops up,
change water [or containers] regardless of the meter reading.
Though it's not USUALLY a factor, there are myriads of pathways to
contaminate your water, even a fingerprint after eating a certain food
[eggs?], where the same fingerprint on a different day has no effect.
I've had batches go deep yellow using very fresh ozonated distilled water,
where, after letting that same jug of water outgas for a few days, made
fine colorless CS . [many bubbles formed on the sides of the jug proving
the existence of dissolved gasses in the water]
Ode
At 08:28 AM 1/27/2006 -0600, you wrote:
Just got a COM-100, EC/TDS/TEMP Combo Meter from SilverPuppy. Looks
like a real nice unit.
My question is, since it has 3 different scales apparently based on
different temperature compensation coefficients, which scale should I
use?
It appears that it is set on NaCl at this time.
By the way, my distilled water reads 1.3 to 1.4 uS. A quart batch run
overnight with magnetic stirring read 20.5 uS this morning. Light
tyndall with laser in incandescent room light and a slight haze visible
to the eye without the laser. I was not able to pull out the electrodes
immediately after the unit shut off since it occurred in the middle of
the night.
Dan
--
The Silver List is a moderated forum for discussing Colloidal Silver.
Instructions for unsubscribing are posted at: http://silverlist.org
To post, address your message to: [email protected]
Address Off-Topic messages to: [email protected]
The Silver List and Off Topic List archives are currently down...
List maintainer: Mike Devour <[email protected]>
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.375 / Virus Database: 267.14.23/243 - Release Date: 1/27/2006
--
No virus found in this incoming message.
Checked by AVG Anti-Virus.
Version: 7.1.375 / Virus Database: 267.14.23 - Release Date: 1/27/2006
--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.1.375 / Virus Database: 267.14.23 - Release Date: 1/27/2006
