Tony Would it not be much easier to calibrate with a precision resistor? 100K Ohm = 10uS 200K ohm = 5uS and so on.
Ivan. ----- Original Message ----- From: "Tony Moody" <[email protected]> To: <[email protected]> Sent: Wednesday, 20 September 2000 20:02 Subject: Re: CS>Measurement of Conductivity > List, > > Make your own conductivity calibration solution. > > To calibrate the meter including probes accurately, a calibrating liquid > is required. A saturated calcium sulphate (CaSO4) solution is eminently > suitable for this purpose: at 20 deg C, this has a conductance of 1976 > uS cm-1 (micro-Siemens per centimetre). The solution is prepared by > mixing calcium sulphate in distilled water until the liquid accepts no > more of the CaSO4. Note, however that CaSO4 is only slowly soluble in > water. > > By adding an identical volume of water to the solution, the conductance > will be halved. Doubling the volume again by adding distilled water will > halved the conductance once more. While calibrating the meter, make sure > that the solution remains at 20 C, because the conductance varies with > temperature. > > Ref. Elektor 304 circuits. #201 Conductance Meter. 910039 - 12 > > > Tony -- 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: [email protected] -or- [email protected] with the word subscribe or unsubscribe in the SUBJECT line. To post, address your message to: [email protected] Silver-list archive: http://escribe.com/health/thesilverlist/index.html List maintainer: Mike Devour <[email protected]>
