Hanna Instruments HI 2002, Инструкция по эксплуатации, Страница: 47 / 52

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Symptoms Problems Solution
No sensor connection.
Sensor model not
recognized. Make certain, 3 mm connector is in all the way by
pushing firmly into probe input.
Slow response/
excessive drift.
Dirty pH electrode.
Clean the electrode and then soak the tip in HI7061 or
HI8061 for 30 minutes.
Readings fluctuate up
and down (noise).
pH: Clogged/
dirty junction. Low
electrolyte level
(refillable electrodes
only).
Clean the electrode. Refill with fresh solution (for
refillable electrodes only). Check cable and connectors.
The meter does not
accept the buffer/
standard solution for
calibration.
pH: Dirty electrode or
contaminated buffer. Follow the cleaning procedure. If still no results, replace
the electrode. Replace buffer.
If the display shows:
“pH” and “‑2.00” or
“16.00” blinking.
Out of range in the pH
scale.
A) Verify that the shipping cap has been removed.
B) Make sure the pH sample is in the specified range.
C) Check electrolyte level and general state of the
electrode.
If the display shows:
“mV” and “‑1000” or
“1000” blinking.
Out of range in the mV
scale.
A) Verify the shipping cap has been removed.
B) Make sure the sample pH is within specified range.
C) Verify electrolyte level in pH sensor is topped off.
D) Verify no bubbles inside pH membrane.
The meter does not
measure temperature.
“‑‑‑‑” is displayed on
second LCD line.
Broken temperature
sensor.
Replace the probe.
The meter fails to
calibrate or gives faulty
readings.
Broken pH electrode. Replace the electrode.
At startup the meter
displays all LCD tags
permanently.
One of the keys is
stuck. Check the keyboard or contact your local Hanna
Instruments Office.
CAL “Prod” message at
startup.
Instrument was not
factory calibrated or
lost factory calibration.
Contact your local Hanna Instruments Office for help.
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