Calibration Mode - Hanna Instruments HI 504 Instruction Manual

CALIBRATION MODE

The calibration mode allows to calibrate the pH/ORP input,
temperature input and 4-20 mA analog outputs.
The controller is factory calibrated for all these parameters.
Periodical calibration of the instrument is recommended, in
particular when greatest accuracy is required and at least bi-
yearly.
It is possible to calibrate the electrode over only one point,
but it is always good practice to perform a 2-point calibra-
tion.
To enter the calibration mode press the CAL key.
Enter the correct password and press the CFM key. If a wrong
password is entered, the instrument returns to the previous
mode.
Note
If the meter is set as an ORP controller (setup item G.00), the
pH calibration, pH reading offset adjustment, and pH offset
and slope are not available. If the meter is selected as a pH
controller, no ORP calibration can be selected.
Note
Any calibration procedure can be aborted at any time by
pressing the CAL key, and the instrument returns to the previ-
ous mode.
The pH/ORP controller can be calibrated through a one-
point or two-point calibration.
The pH calibration can not be performed if the pH electrode
is broken or leaking or the reference electrode is broken or
dirty and an error is active. The ORP calibration can not be
performed if the "Reference electrode broken or dirty" error is
active. For pH calibration the temperature probe should be
connected to the process meter.
All calibrations refer to the process controller. No calibration
for the Digital Transmitter can be performed by the process
controller, but the Digital Transmitter Calibrator must be used
for that.
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The pH and ORP calibrations can not be initiated while the
process controller is configurated to take measurements from
the Digital Transmitter.
pH CALIBRATION
It is recommended to perform pH calibration when the probe
is replaced and after any cleaning action.
To perform any pH calibration procedure, the instrument has
to be set as pH controller.
Initial Preparation
Pour small quantities of pH 7.01 (HI 7007) and pH 4.01
(HI 7004) or pH 10.01 (HI 7010) solutions into individual
beakers. If possible, use plastic beakers to minimize any EMC
interference.
For accurate calibration use different beakers for each buffer
solution, the first one for rinsing the electrode and the second
one for calibration. By doing this, contamination between
buffers is minimized.
• Enter the calibration mode, select the pH calibration (by
moving through the menu with the æ
press the CFM key.
• Choose the pH buffer set between the two available ones:
the standard set (4.01, 7.01, 10.01) and the NIST set (4.01,
6.86, 9.18). For the standard set confirm the "Std"; for the
NIST set confirm the "niSt" (use the æ and
between the two options).
RINSE CALIBRATION
HI 7007 HI 7007
and keys), then
keys for select
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