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11
• Adjust the slope trimmer until the ammeter reads 8.58 mA for
HI 8614
and
HI 8614L
or the display shows “4.01“ at 25 °C.
For other buffer temperatures, refer to page 12 for the appropriate
mA / pH reading.
If you are using pH 10.01 buffer
solution adjust the slope trimmer
until the ammeter read 15.43 mA at
25 °C (77 °F) or the value indicated at
page 12.
FOR HI 8614L ONLY
The Display Module is factory calibrated, so that the LCD display
results are referred to the 4-20 mA loop current (e.g. LCD displays
0.00 pH when the loop current is 4.00 mA and displays 14.00 pH
when the current is 20.00 mA).
Under normal application, adjustment on this module may not be
necessary.
If routine check is required, the following procedures shall be performed.
• Follow the procedure at page 10 to perform calibration on the
transmitter module (using a ammeter).
• Simulate a 4.00 mA loop current for the transmitter (i.e. 0.00 pH
as Electrode input) and check for display reading.
• Simulate a 20.00 mA loop current for the transmitter (i.e.
14.00 pH as Electrode input) and check for display reading.
Note:
When
HI 8614
or
HI 8614L
instruments are used in
conjunction with the new Hanna indicator
HI 8510
or
controllers
HI 8710
and
HI 8711
, the calibration can also
be performed on the indicator/controller. In this case slight
calibration adjustment can be made on the indicator/
controller even if the whole system calibration is advised,
always starting from the transmitter.