Hanna Instruments HI 700 Series - Manual (Page 21)

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ANALOG INPUT CALIBRATION
The analog input is already factory calibrated. However, the
user may also perform a 2-point calibration at 4 and 20 mA.
It is sufficient to perform the calibration on one range only.
• Connect a mA simulator (e.g. HI931002) to the analog
input of the controller (#12 at page 7)
• Press and hold first CFM and then
CAL to enter the analog input cali-
bration mode.
• Execute the password procedure.
• Select code 0 via the arrow keys for analog input calibra-
tion and confirm with CFM. CAL will blink on the LCD.
• The secondary LCD will display “4”
for the first calibration point. The pri-
mary LCD will display the conductivity
reading.
• Set the mA simulator to 4 mA and wait for the reading to
stabilize, CAL will stop blinking and an intermittent CFM
will prompt the user to confirm the calibration.
• If the reading stabilizes at a reading significantly variant
from the first calibration point, an intermittent ERROR will
prompt the user to check the input.
• If everything is satisfactory the sec-
ondary LCD will display “20” for the
second calibration point.
• Set the mA simulator to 20 mA and wait for the reading to
stabilize, CAL will stop blinking and an intermittent CFM
will prompt the user to confirm the calibration.
• Press CFM to confirm. The meter will
return to normal operational mode.
Calibration procedure may be interrupted by pressing CAL
again at any time. If the calibration procedure is stopped this
way, or if the controller is switched off before the last step, no
calibration data is stored in non-volatile memory (EEPROM).
TEMPERATURE CALIBRATION
The controller is factory calibrated for temperature. However,
the user may also perform a one point temperature calibra-
tion. This procedure is to calibrate the offset only; the slope
will remain as factory calibrated.
• Prepare a beaker containing a solution at a given tem-
perature inside the range of the meter.
• Use a Checktemp or a calibrated thermometer with a reso-
lution of 0.1° as a reference thermometer.
• Immerse the temperature probe in the beaker as close to
the Checktemp as possible.
• Press and hold first CFM and then
CAL to enter the temperature calibra-
tion mode.
• Execute the password procedure.
• Select code 1 via the arrow keys for temperature calibra-
tion and confirm with CFM.
• CAL will blink on the LCD. The mea-
sured temperature will be displayed
on both the primary and secondary
LCD.
• Use the arrow keys to set on the secondary LCD the tem-
perature read by the reference thermometer.
• When the reading has stabilized at a value near the cali-
bration point, CAL will stop blinking and an intermittent
CFM will prompt the user to confirm the calibration.
• If the reading stabilizes at a reading significantly variant
from the first setpoint, an intermittent ERROR will prompt
the user to check the beaker or bath.
Calibration procedure may be interrupted by pressing CAL
again at any time. If the calibration procedure is stopped this
way, or if the controller is switched off before the last step, no
calibration data is stored in non-volatile memory (EEPROM).