10% of WHAT? Is that +/- 10% of the max read range or +/- 10% of 1 PPM? [See the problem?]
+/- 10% of 100% is like 10 PPM and that's a big chunk of 15 PPM. "Specs" can be tricky. [They don't always say what you think they do] *Silver Range* 0.000 to 1.000 mg/L (ppm) [But 15 PPM is WAY OVER that range and +/- 10% has to do with the instrument, not the reagent] The Hanna meter calibration fluid has a temperature deviation chart on it, but the meter specs say the meter is 'temperature compensated' ..so, why the chart? It took a MONTH going round and round with Hanna Tech for them to say it's the temperature of the METER that is compensated for...not the calibration sample. [After telling me I was too stupid to ask questions and saying I didn't see what I was seeing] ..and if the meter is colder or warmer than the sample, that dog hunts all over the place as it warms or cools the sample. Holding the sachet in your hand while calibrating the meter screws it ALL up as the reading climbs and climbs before your eyes. Finally figuring all that out [on my own, thank you], their sachel proved their big bottle of "reagent" was off by exactly 50%....[around $30 worth] and they wouldn't replace it. I learned the hard/long way to make sure both the meter and the sample are at the *same *temperature...and STAY that way while using the meter. [THEN refer to the temperature deviation chart] How easy is it to just SAY that in the first place ? DUH!!!! [But NOOO....so, maybe even Hanna Tech didn't know that?] HM Digital meters have a thermometer built in. A really BIG Thermometer is a TherPOPiter? [;-)] ode On Wed, Jul 8, 2020 at 10:20 AM Marshall <mdud...@king-cart.com> wrote: > The unit measures between 0 and 1 ppm. I have to dilute it to get it in > that range. Specifications give an accuracy of 10%, so 60% to 90% error is > way out of line. > > Marshall > > On 7/8/2020 8:36 AM, Ode Coyote wrote: > > Titration is not NEARLY accurate enough to measure 15 PPM > Even an AA Spectrophotometer has great difficulty at low concentrations > and 3 runs of the same sample averaged is the procedure > > ode > > On Tue, Jul 7, 2020 at 7:54 PM Marshall <mdud...@king-cart.com> wrote: > >> I am helping my son in law with his colloidal silver production. But I >> am running into something I don't understand. He has been using a hanna >> pure water meter to measure the ionic ppm. He has been applying a 1.1 >> correction factor, that is brewing for a 14 uS, to get 15 ppm. >> >> He just ordered and received a hanna silver ion colorimeter and we have >> been testing with it. When we dissolve the CS silver in nitric acid, >> the readings are way off, near zero. I am going to contact Hanna on >> that, I am assuming that either the nitrate ion, or the pH is messing it >> up. >> >> But testing some week old CS, I am getting about 6 ppm on the >> colorimeter, but 12 uS (or about 13 ppm) on the conductivity meter. I >> don't know which one is wrong. Anyone have experience with the >> colorimeter? >> >> Thanks, >> >> Marshall >> >> >> -- >> The Silver List is a moderated forum for discussing Colloidal Silver. >> Rules and Instructions: http://www.silverlist.org >> >> Unsubscribe: >> <mailto:silver-list-requ...@eskimo.com?subject=unsubscribe> >> Archives: >> http://www.mail-archive.com/silver-list@eskimo.com/maillist.html >> >> Off-Topic discussions: <mailto:silver-off-topic-l...@eskimo.com> >> List Owner: Mike Devour <mailto:mdev...@eskimo.com> >> >> >> >