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For calcium reactors without an opening for a pH sensor, the sensor has to be installed inside
the water stream leaving the calcium reactor, by means of a suitable device. Settings as
described above.
Note on handling pH sensors
The pH sensor is the most delicate part of the whole measuring equipment and therefore
needs special care in handling. If the following few handling tips are followed, the sensor will
provide accurate measurements over a long time.
Handling and care
·
Avoid hard impacts and take particular care when handling the delicate sensor tip
made of special glass.
·
Avoid kinks in the sensor cable.
·
Never allow the sensor tip to dry out.
·
Sensor tips which have accidentally dried out can often be reactivated by being
placed in storage or revitalisation solution for 24 hours or longer. The same often
applies to sensors which can no longer be successfully calibrated. Pour about 2 – 3
cm of JBL Storage and Revitalisation Solution in the storage tube supplied with the
sensor, place the sensor in the solution until the tip is submerged and tighten the
screw lid with the seal ring by hand. For safe storage, place the storage tube with
the sensor in the storage hole on the calibration stand.
·
Sensors which are not in use for a longer period of time should always be placed in
JBL Storage and Revitalisation Solution, as already described.
·
Never fully immerse the sensor in the water. The sensor cap and cable connection
should always be out of the water. Ideally the sensor should be immersed to the
top of the writing on the sensor shaft (JBL pH Sensor).
·
The sensor should be positioned in the darkest part of the aquarium to prevent
algae growing on the tip. Algae growth could lead to incorrect measurements.
·
Do not lay the sensor cable next to mains current-bearing cables for long distances.
·
If the sensor is accidentally pulled out of the water or the water level drops
signi cantly, the device will measure incorrectly and adjust accordingly. This is
dangerous for the sh. Regular checking is recommended.
·
Any dirt that has accumulated on the tip of the sensor can be carefully wiped o
with a soft cloth, never rub vigorously, just dab. Store the sensor in JBL Storage and
Revitalisation Solution for 24 hours, then calibrate.
Service life of the sensor
pH sensors automatically deteriorate over time, and this is referred to as ageing. Ageing
begins from the day of manufacture. The voltage delivered by the sensor tip and recorded
by the measuring device and transformed into pH units gives an indication of the condition
of the sensor. The voltage in mV (millivolt) can be read directly from the JBL PROFLORA pH
control Touch.
When dipped into pH 7.00 bu er solution, a brand-new sensor shows a voltage of 0 +/- less
mV. This voltage changes per full pH unit by about 59 mV in a positive or negative direction,
depending on whether measurements are above or below 7.00. When a new sensor is
dipped into pH 4.00 bu er solution, the voltage is approx. 177 mV. If the sensor has aged,
voltage measured at pH 7.00 usually shifts into the negative range. For example, in 7.00
bu er solution, -28 mV is measured. In addition, the voltage di erence per full pH unit
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