Do I need to Calibrate an ORP electrode?
No. ORP electrodes do not need calibration with the meter such as pH. Still, ORP electrodes need to be conditioned prior to use. When the electrode is new, soak the tip in warm tap water. This will enhance the flow of the reference junction. To check function of the electrode, immerse the tip in ORP solution HI 7021L or HI 7022L. The reading should be +/- 50mV from the value indicated on the bottle. If the reading is not within the +/-50mV, oxidizing or reduction treatment with HI 7092 or HI 7091 is required. It will also prepare the electrode's surface and speed initial response time. Since in-line process electrodes are already in a solution, a simple test with either HI 7021L or HI 7022L will show you the electrode's condition. Should your probe not be accurate enough after conditioning & testing, follow the cleaning procedure.