User Guide

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7 ORP CALIBRATION
IMPORTANT: When Calibration mode is entered, controller automatically goes into
a “HOLD” mode where the 4-20 mA output freezes and relays are de-activated (if it
was in an activated condition). Upon return to measurement mode, both 4-20mA
output and relay activities resume, depending on settings.
mV (ORP) values may be offset at up to ±150 mV to agree with a calibration
solution or an established work standard.
1. Press CAL / ENTER key to directly access the Calibration mode when the
unit is in ORP measurement mode.
NOTE: Instead of pressing the CAL/ENTER key, you can also enter the Calibration
mode using the password code procedure as explained in Section 5.
2. Controller will blink with un-calibrated mV output of your electrode.
3. Determine the mV value of your solution with an accurate meter (such as the
pH 6).
4. Press the or keys to offset the mV value on the controller display to
match the value of the solution you are measuring.
5. Press ENTER. The display flashes “DONE”. Press ENTER again to return to
measurement mode.
NOTE: You can view the mV offset in the Setup program, P5.0.
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