View Full Version : ORP probe calibration easier?

12/04/2005, 07:57 AM
While I owned a PinPoint ORP meter, I always calibrated the probe with a 1:6 solution of RO/DI water to bleech. It gives a dead on 700 mV reading. Very cheap, easy to make, and very readily available. NOw I have the ORP probe with my AC2 and it has a 2 point pH quinhydrine? ORP calibration that seems extremely and completely unnecessarily complicated for what it is. My question is, can I just use the same 700 mV calibration solution I was using before for both pH points and adjust the numbers to have it read 700?

By the way, I did not invent the ORP bleech:water solution. I got this from the same PinPoint people, which now I see are packaging it and selling it.

12/04/2005, 02:01 PM
I don't know about this calibration method, but assuming that it is an accurate calibration standard it can be used. The one problem I see with this method is its value is about two times greater than the value in your tank, and it is a one point calibration.
Here is a way to manually:
- With the controller in the run display place the probe in the 700mV reference solution. Wait several minutes for the probe to stabilize. Note the value. Let y = 700 - orp_reading.
- Go to the second screen of the selftest display. Press the up button twice, the down button twice, and then the select button. You should now be in the manual cal menu.
- go to the ORP manual cal. Adjust the offset up or down by 'y'.
- exit the manual cal menu.
- Go to the run display. With the ORP probe still in the 700 mV calibration solution, the ORP should read 700.


01/14/2006, 04:51 PM
I can't get to the manual calibration screen. Please explain how to get "to the second screen of the selftest display".