Hello Jhon, Following is the instruction sheet we ship with each PWT meter. Perhaps the issue will be more clear now. Perhaps others will argue the point. In any case, it is not really clear which methods are the best to measure the PPM of CS. However, the PWT meter gives the closest consistent readings we have seen at an affordable price. It is a good tool to show consistency of CS batch to batch, etc.
"Instructions on use of the PWT meter The PWT meter is designed to measure purity of water. That is, it measures conductivity of water. This is measured in micro siemens which is abbreviated µS. When you insert the meter into your distilled water, it will read the conductivity and if the reading is less than 2.0 to 3.0 µS the water is suitable for use in making CS. This means it has very little mineralization. Minerals can combine with silver in the process to form silver compounds rather than colloidal silver. We recommend using only steam distilled water to make CS. Measure the uS of your water before making CS. Make note of the value. Once you have checked your water and made your CS, insert the PWT into the CS. It will read directly in PPM minus the reading of the water previously recorded. We had several samples of our CS analyzed by two different laboratories using the atomic absorption method and tests at one of the labs was done two different ways on each sample. In the first case, the CS was tested without benefit of "digestion" . That means the CS water samples were analyzed by the machine without anything being done to the samples. Then the second set of samples were digested and the tests were run again. Digestion means to take the CS and combine it with nitric acid or aqua regia (nitric and hydrochloric acids) in order to completely dissolve the silver in the dispersion. This was to done to assure that all the silver is in a state which can be seen by the testing machine. The CS acid combination is boiled to dryness. Then enough distilled water is added to bring the liquid volume back up the original quantity. The silver is now a dissolved salt and is in solution. In the first test, readings from undigested CS were made of part of the same set of samples which were subjected to digestion. The PPM reading of these samples read at about 55% of the digested samples. So, if you read CS with your tester its reading will correspond quite closely to samples which were digested; or will read about 45% higher than samples which were not digested. We believe the digested samples more closely reflect what the real PPM is. Therefore we suggest you use the PWT reading as the true value of your CS PPM. Or, you may use the more conservative figure of 55% of the reading for your CS value. Initial readings will be higher than after a waiting period for the particles to evenly disburse throughout the water. Best results are obtained when you wait 24 hours for the CS to stabilize. Your PWT meter is guaranteed by the factory for a period of 1 year. If you have any problems with the unit, package it so it is protected from damage and ship it to Hanna Instruments along with a copy of your invoice from us. When calibrating your PWT, let the calibrating solution reach room temperature. The PWT has a temperature probe to adjust for different temperatures but it will "hunt" if the calibrating solution is changing temperature such as being brought in from a different environment." I hope the issue is a bit more clear now. Trem www.silvergen.com Constant Current Colloid Generators ----- Original Message ----- From: aka Jhon <maj.yo...@ellijay.com> To: <silver-list@eskimo.com> Sent: Friday, April 14, 2000 4:02 AM Subject: Re: CS> PPM > I must be really dense,,I have read the info from Silvergen, and this > list,,and what I gather is: > ...the Hanna PWT is right on on its reading,,also it is 45% too high.. > ,,how can it be both??? > > ----- Original Message ----- > From: Trem Williams <t...@silvergen.com> > To: <silver-list@eskimo.com> > Sent: Thursday, April 13, 2000 6:41 PM > Subject: Re: CS> PPM > > > | Hello Robert, > | > | I agree very closely with your information. We market the Hanna PWT and > | tell our customers the meter reads correctly on samples we have had > analyzed > | by the atomic absorption method but if they want to follow the information > | given by Hanna, to multiply the reading by .55 to get their reading. In > any > | case, it's right on or 45% high. I really don't see this as a critical > | problem since we're speaking only of a few parts per million. This is > | briefly covered on our PPM page at our web site. We do not mention the > 55% > | effect since we are content to accept the AA test as being accurate. > | However we do point this anomaly out on the instruction sheet we provide > | with the PWT. > | > | What is important is the fact a person can tell from batch to batch what > | they have made. The PWT is the best low cost solution to making reliable > CS > | from one batch to the next and confirming the results. The TDS-1 is > | unacceptable for measuring PPM. > | > | Trem > | | > | > | ----- Original Message ----- > | From: Robert Dohr <beld...@netscape.net> > | To: <silver-list@eskimo.com> > | Sent: Thursday, April 13, 2000 3:06 PM > | Subject: Re: CS> PPM > | > | > | > Greetings Seekers; > | > Ivan, our numbers are similar (.59 to .57) but I think you may have them > | > backwards. The instructions from Hanna and what my lab results confirmed > | was > | > .59PPM/us. or take the reading in us/cm times .59 to get PPM. In my case > | > 25.5us/cm = 15 PPM. per lab test. Also the us/cm will drop with time for > | the > | > first 10-12 hrs, not rise. This appears to be due to the CS dispersing > | > throughout the DW. Immediately after making a batch the CS is > concentrated > | > around the ion path between the electrodes. A reading taken at this time > | will > | > be high and erratic. After sitting overnite the reading will be lower > but > | > stabile. After this initial dispersion the reading should not change > | futher. I > | > have CS that is now several months old that still reads within 1 us/cm > of > | when > | > it was made. As for accuracy my PWT measures in .1us/cm up to 99.9us/cm. > I > | > calibrate it using a solution from Hanna that measures 84us. It comes in > | small > | > pouches that you tear open and insert the meter. Use once and throw > away. > | > NAMASTE' > | > Beldohr > | > > | > ____________________________________________________________________ > | > Get your own FREE, personal Netscape WebMail account today at > | http://webmail.netscape.com. > | > > | > > | > -- > | > The silver-list is a moderated forum for discussion of colloidal silver. > | > > | > To join or quit silver-list or silver-digest send an e-mail message to: > | > silver-list-requ...@eskimo.com -or- silver-digest-requ...@eskimo.com > | > with the word subscribe or unsubscribe in the SUBJECT line. > | > > | > To post, address your message to: silver-list@eskimo.com > | > Silver-list archive: http://escribe.com/health/thesilverlist/index.html > | > List maintainer: Mike Devour <mdev...@id.net> > | > > | > > | > >
