Dave As you are probably aware, one unit is the reciprocal of the other. As a rough guide, you can say that the ionic contaminants in your water are roughly proportional to the conductivity, if you offset the minimum value of 0.056 µS-cm (at 20°C). Practically, therefore, if your scale is, say, 0 to 10 µS-cm, it is approximately linear to the contaminants. On the other hand, if your resistivity scale is 0 to 20 Mohm-cm, your most useful part will be non-linearly cramped up between, say, 10 and 18 Mohm-cm and a relatively large change in contaminants will result in a small change in reading at the upper end. Go for conductivity, every time. Brian Dave Abbott wrote: > > Hi Technet members > > I have a stencil and mis-print cleaner on-site which has a water > purification circuit attached. It consists of a Carbon and a D.I. cylinder > and I need to plumb in a meter for measuring the purified water. I have > only ever used resistivity systems previously, but have now discovered > conductivity meters. The only thing I have been told about them is that > they can measure to a tighter degree than resistivity meters. If anybody > can enlighten me unto which system would suit my application best, then it > would be greatly appreciated. > > Thanks in advance > > Dave Abbott > Manufacturing Engineer > Marconi Communications > > --------------------------------------------------------------------------------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8d > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL > Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 > --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------