User's Manual

21
• If the temperature of the buffer solution is not 25°C (77°F), refer to
the chart at the end of the manual for the appropriate buffer value
at a given temperature and adjust the trimmer accordingly.
SLOPE ADJUSTMENT:
• Rinse the electrode (and ground probe)
thoroughly with water and immerse the
bottom 4 cm (1.5”) in a pH 10.01
(HI 7010) or a pH 4.01 (HI 7004) buffer
solution.
• Stir the electrode and wait for the display to stabilize before
adjusting the "SLOPE" trimmer (see 6 - Functional Diagram) to
display pH 4.01 (or 10.01) on
the LCD if the temperature of
the buffer solution is at 25°C
(77°F). Otherwise, refer to the
chart at the end of the manual
for the appropriate buffer value
and adjust the trimmer accord-
ingly.
The pH calibration is now complete.
Make sure that the probe has been properly connected and
wired to the controller (see preceding pages) and that the meter
is plugged to the mains.
Calibration should be ideally performed at a temperature similar
to that of the liquid to be monitored.
ZERO ADJUSTMENT:
• Leave the probe in the air and make
sure that it is dry.
• The LCD should show 0. If necessary
adjust the "ZERO CAL" trimmer to dis-
play zero (see 12 - Functional Diagram)
SLOPE ADJUSTMENT:
• Pour sufficient amount of a known conductivity or TDS solution in
a beaker. The solution should ideally be close to the sample
stream to be monitored. For example, when using the HI 9913,
choose HI 7031L with a 1.41 mS/cm at 25 °C if the measure-
4cm
(1½")
HI 7004
pH
OFFSET SLOPE
ALARM
ON
OFF
4.01
SLOPE CAL
ALARM
ON
EC
mS
ZERO CAL
0
ADJUSTEMENT OF SETPOINTADJUSTEMENT OF SETPOINT
ADJUSTEMENT OF SETPOINTADJUSTEMENT OF SETPOINT
ADJUSTEMENT OF SETPOINT
CONDUCTIVITY/TDS CALIBRATIONCONDUCTIVITY/TDS CALIBRATION
CONDUCTIVITY/TDS CALIBRATIONCONDUCTIVITY/TDS CALIBRATION
CONDUCTIVITY/TDS CALIBRATION