Hanna Instruments HI 2221 User Manual
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mV CALIBRATION
V CALIBRATION
V CALIBRATION
V CALIBRATION
V CALIBRATION
(for technical personnel only)
All the instruments are factory calibrated for mV.
Hanna’s ORP electrodes are interchangeable and no mV calibration is
needed when they are replaced.
If the mV measurements are inaccurate, mV recalibration should be
performed.
For an accurate recalibration, contact your dealer or the nearest Hanna
Customer Service Center, or follow the instructions below.
A two-point calibration can be performed at 0.0 mV and 1800.0 mV.
• Attach to the BNC connector a mV simulator with an accuracy of
±0.1 mV.
• With the instrument off, press and hold down the CAL & ºC
keys, then power on the instrument. The “CAL” tag will appear and
the secondary LCD will show “0.0 mV“.
• Set 0.0 mV on the simulator.
When the reading is stable and close to the selected calibration
point, “READY” tag will appear and “CFM” tag will blink.
• Press CFM to confirm. The secondary LCD will display
“
1800 mV
“
.
• Set 1800.0 mV on the simulator.
When the reading is stable and close to the selected calibration
point, “READY” tag will appear and “CFM” tag will blink.
• Press CFM to confirm. The
instrument
returns to measurement
mode.
Note: If the reading is not close to the selected calibration point,
“WRONG” tag will blink. Verify calibration condition or contact
your vendor if you can not calibrate.