Aging pH meter false reading 'high or low' survey

[Silver_Is_Money]

As my Apera pH60 meter, which was used exclusively for 3 years for mash pH measurement at room temperature, aged, it began becoming progressively more unstable and more difficult to calibrate such that it held calibration well over time. And the mash pH readings I got from it began to consistently be noticeably off to the low side of historical expectations.

Thus, I would like to begin a survey to see if there is, or is not, a trend for aging pH meters used pretty much exclusively for mash pH measurement to consistently drift toward false low pH indication or alternately toward false high pH indication.

 

[bracconiere]

My manual calibrated milwaukee MW-101, is spot on all the time....it just gets slower......i replaced the probe recently, but only for speed. (at least that's what sticking it calibration solution tells me)

 

[Robert65]

IME Hanna pHep5 meters also increasingly drift low, especially at the low end, and are slower to calibrate (such that they can be said to calibrate, given the drift.) That said, mine (I've had two) had this problem to a lesser degree when new, they just got worse over time, and replacing the electrode somehow didn't help.

My rather new MW101 is very easy to calibrate, and rock steady. Hope it stays that way.

 

[bracconiere]

My rather new MW101 is very easy to calibrate, and rock steady. Hope it stays that way.

having the dials to adjust is nice, my first ph meter wouldn't "auto" calibrate after just a few months. why i opt'd for the manual....MW101's are tough!!

 

[mabrungard]

I just replaced the probe on my MW-101 and it needed it. I hadn’t been using it for several years since Hanna gave me one of their Halo units. I checked the 101 out recently and it would calibrate, but it was slow. It would not compare with the Halo readings. That old probe was probably 8 plus years old.

Since the original probe had such longevity, I bought another. Upon recalibration, the new probe compares very closely with the Halo.

For a modestly priced meter, the 101 performs very well and is durable. I also agree that having manual calibration is not a bad thing at all. It actually makes the meter even more reliable.