[Ian Lancaster]

Some lamebrain got into my van a few weeks ago and stole: all my invoices, my lunchbox with one sandwich in it, my service record book for the van, and my TDS meter (hand held).

Apart from the fact that it must have been a particularly backward retard (what the hell was he/she going to do with that lot, especially as he/she wouldn't have had the foggiest what a TDS was for) it meant I had to invest in a new lunchbox and TDS meter, as well as print up a load of new invoices.

From the start the new TDS meter showed a reading of 002, even though I've got a pretty new pumped 40-40 system followed by a big DI cylinder with new resin in it.  After a week or two the reading went up to 004.  Being a bit suspicious I bought a bottle of calibration fluid, guaranteed TDS 342.  My meter showed a reading of 395, a discrepancy of 13.42%

I've had a look and I can't see any way to adjust it, though I've e-mailed the supplier for advice.

Anyway, the point is:

Do you trust your TDS meter, and if so why?

Would you trust calibration fluid to be what it says on the bottle, i.e. 342 ppm?

[Chris Galloway]

I would hope my tds meter was calibrated properly at the manufacture stage. But if you cant trust calibration fluid who the heck are you gonna trust!?

[alanwilson]

Ian

Calibration fluid is EXACTLY what it says, if it says 342ppm then that is what it is as it is used to calibrate with (its all made from standard soln)

Look on the back of the meter, there should be a small hole somewhere near the to of the unit - behind it is a small screw, adjust that screw until the reading says 342 (obviously while in the soln)

[elite mike]

hi ian
i have ro man in line tds meter and pure freedom hand held

both show different readings

do i trust them   no

i have cleaned with readings of 15 tds with no probs

mike

[Captain Scarlet]

Ian, most meters can be adjusted with a screw driver, i believe behind the batteries.

[dai]

I don't use resin when the meter gives a reading of 002, well I do but only in the first in line vessel.
I trust the meter because I have always had perfect results with it. Irrespective of what the true reading may be, I know I will get good results below 002.

[Slash]

I have two handheld tds and both are different readings!

[matt]

as long as its below 010 no issues

[mci services]

where do you buy calibration fluid and how much does it cost

[jouk45]

where do you buy calibration fluid and how much does it cost

you can buy it from ro man stu.
http://www.ro-man.com/shop/product_info.php/cPath/29_81/products_id/133

[mci services]

where do you buy calibration fluid and how much does it cost

you can buy it from ro man stu.
http://www.ro-man.com/shop/product_info.php/cPath/29_81/products_id/133

thanks jouk