[jeffmoonchop]

Hi I just plugged in a new probe and tried to calibrate, but the pH reading is two units below the actual buffer pH, so when I try to calibrate with a pH 7 buffer, it thinks its pH 4 because its reading pH 5.

I tried adding manual buffers in for calibration where I told it when the pH of the buffers are, I thought this would bring it back into alignment but when I tried to automatically calibrate again I was getting the same problem.

Do I have to calibrate with manual buffers every time or is there another way to get the probe to read the correct pH?

thanks

[Borek]

Can you check with some other electrode if buffers are OK and if the pH meter works OK?

[jeffmoonchop]

Yes they are, this is a replacement probe the previous one wasn't perfect but it was much closer. We had a similar thing happen to another new probe on a different meter. They are Calomel probes if that helps.