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10. ORP Measurement
ORP stands for Oxidation-Reduction Potential, measured in mV. It’s also called redox. ORP is a
measure of the cleanliness of water & its ability to break down contaminants. A separate ORP probe
(ORP60-DA) needs to be installed to be able to measure ORP.
Power on the PC60-Z tester, unscrew the original probe, and install the ORP60-DA probe, then the
tester will automatically switch to ORP measurement mode (Refer to Section 14 for how to replace
a probe).
Rinse the probe in distilled water and dry it. Dip the probe in sample solution, shake for a few seconds,
and allow it to stand still. Get the ORP readings after
appears and stays on screen.
11. Probe Cleaning
1) The tester is only as accurate as the probe is clean. Always thoroughly rinse off the probe before
and after each measurement with pure water in a container or with a wash bottle.
2) For tough contaminants, detach the sensor shield, soak the probe in Apera probe cleaning
solution (AI1166) or detergent water for 30 minutes. Then use a soft brush to remove the
contaminants. Afterwards, soak the probe in 3M KCL soaking solution for at least 1 hour. Rinse it
off, then re-calibrate the tester before using again.
12. Probe Storage
1) Under regular usage (daily or weekly use), make sure the probe cap is wet, and tightly close the
cap with the O-ring.
2) For long-term storage (you are not going to use the product for a while), add 3M KCL soaking
solution to the Fill line in the probe cap and store the probe in it. Close on the probe cap tightly
with the O-ring.
3) If you find white crystals inside or outside the probe cap, it is perfectly normal. It is the 3M KCL
soaking solution that crystalizes over time by its nature. Just rinse them off and add in new soaking
solution. This chemical is not poisonous nor dangerous, and the probe’s performance will not be
affected at all.
4) NEVER store the probe in pure water like tap, RO, distilled, or deionized water as they could
damage the pH probe. If this happens, immediately soak the pH probe Apera 3M KCL soaking
solution overnight, then re-calibrate it before using. Pure water is only for rinsing the probe.
