Comments on: Calibrating and Caring for your pH Meter

By: Archie Chua

Archie Chua — Wed, 05 Oct 2011 15:07:27 +0000

we have purchased this same brand of ph meter, the HM digital PH-200, as if we have followed throughly what is in the user guide but we are having problems with the readouts and calibration it always displays near 7ph. could you pls. give us remedial solution to this query ASAP

By: Justin Balesteri

Justin Balesteri — Fri, 20 May 2011 16:58:11 +0000

I too have purchased the PH-200 from HM Digital. I am currently mailing it back for the second time. In all fairness, the company admitted that there was a defective part in the first meter that I purchased that lead to incorrect calibration and readings. However, this time it is not a calibration issue per se. I have to keep calibrating the meter as it will not stay calibrated. I will calibrate it to 4 or 7 or BOTH and check the same sample 10 times and get 8 readings. That are as far as one whole number off. Usually it is about a .5 variance, which is completely unacceptable. I only have a tolerance of a few hundreths. I find it kind of sad that when I go on the site, they list this article for care and maintenance, but the only comment here is a comment about someone else that has experienced the same issue I had. I will mail it back in this time and let everyone know how it worked out.

By: David Naughton

David Naughton — Sat, 01 Jan 2011 09:48:25 +0000

I have purchased the Ph tester, Model PH-200, and have had to bring it back two times for exchange within three weeks after purchase because the meter gives the wrong reading.
I have taken great care to follow all of the instructions to the letter and have experienced the same failure. It levels out at 10 and will not manually lower to the point of 7.01 / the buffer without flatlining as it were. I am at my wits end and do not know what else to do.
Any suggestions? Could batteries be the cause?
Reads perfectly one day, the next, it reads 10.00 in the very same solution. What gives?
Thanks