Apera Instruments LabSen 221 User manual

LabSen® 221 Combination pH Electrode
for Viscous and Low Ion Concentration Samples
User Manual
LabSen® electrochemical sensors are premium pH electrodes with manufacturing technology and
key components imported from Switzerland. The LabSen®221 Combination pH Electrode is
designed for precise pH measurement in viscous and low ion concentration samples.
This probe has the following features:
Impact-resistant membrane (see the right picture), there is no danger of
electrode breakage during normal use.
Movable sleeve, able to adjust infiltration rate of electrolyte.
Blue gel inner solution, does not flow and will not cause a bubble.
Long life reference system, has better stability and service life.
1 Technical Data
Measuring Range
(0 ~ 14) pH
Electrolyte
3M KCl
Temperature Range
(-5 ~ 80)°C
Soaking Solution
3M KCl
Shaft Material
Lead-free Glass
Electrode Dimension
(Ø12×130) mm
Membrane Shape
Cylindrical
Connector
BNC
Reference
Long Life
Cable
Ø3×1m
Junction
Movable Sleeve
2 How to Use the Movable Sleeve
As shown on the right picture, reference solution flows out of the
small hole, seeps through the tapered surface of movable sleeve.
You may adjust the degree of firmness when use, push up the
movable sleeve to loose. If it is too tight to push, please referring to
the right picture: insert the probe into the round tube (the accessory
comes with the probe), and push down the probe, then the movable
sleeve will be loosen. Please pay attention to remove the rubber
plug when adjusting the movable sleeve, enables reference solution
flowing out of the small hole; then slowly rotate and tighten the
movable sleeve, so that there will be no air remain in the tapered
surface of movable sleeve, which can greatly influence the correct
measurement of the probe.

3 Usage and Maintenance
1. When measuring, please unscrew the sleeve cap, pull out the electrode and rinse it with deionized
or distilled water. After using, please put the electrode back into the bottle and screw tight the cap.
2. Prior to measurement, remove the blue rubber plug to maintain proper air pressure of the
reference solution, keeping consistent flow rate of the reference solution and stable potentials of
the junction.
3. After a period of usage, the reference solution will run low. Whenever the level falls to 1/2 height
of the electrode, add 3M KCL solution to the refilling hole with a syringe or pipette.
4. If reference solution is contaminated and needs replacement, unplug the blue rubber plug, loosen
the movable sleeve (see section 3), the reference solution will flow out quickly. Once the reference
solution runs out, use a syringe to add purified water through the refilling hole to rinse the
electrode cavity; then rinse again with 3M KCL to remove the remaining purified water; Tighten
the movable sleeve, refill 3M KCL solution with a syringe; then loosen the movable sleeve to let
the solution flows out a bit, and slowly twist it clockwise to tighten, so that air can be avoided in
the surface of movable sleeve.
5. Drop speed of reference solution decides by the glass sleeve tightness, the tighter the slower.
Electrodes must recalibrate upon tightness adjusted. For viscous or low ion concentration
solution measuring, requires fast speed.
6. The connector of the electrode should be kept clean and dry. If contaminated, please clean it with
medical cotton and absolute alcohol and blow dry to prevent the short circuit of the electrode and
slow reaction of electrode.
7. The electrode’s measuring tip should be soaked in the storage sleeve containing 3M KCL storage
solution to keep the membrane hydrated and junction unblocked. Clean the sleeve and replace
the storage solution if the storage solution gets turbid or mildewed. The electrode should never
be soaked in purified water or buffer solution for long.
8. Please avoid measuring dehydrated medium like strong acid or alkaline solution, absolute ethyl
alcohol and concentrated sulfuric acid. In case of measuring such solution, please try to reduce
the immersion time and clean it carefully after use.
9. After 1-year of use, we recommend replacing the electrode for best accuracy.
Before pulling out or putting back the
electrode, make sure to fully loosen the blue
cap on the storage sleeve so that the
electrode can move in and out smoothly.

4 Limited Warranty
We warrant this electrode to be free from defects in material and workmanship and agrees to repair
or replace free of charge, at option of APERA INSTRUMENTS (Europe) GmbH, any malfunctioned
or damaged product attributable to responsibility of APERA INSTRUMENTS for a period of six
months. Warranty period is the time limit to provide free service for the products purchased by
customers, not the service life of the tester or electrodes.
This limited warranty does not cover any damages due to:
I. transportation;
II. storage;
III. improper use;
IV. failure to follow the product instructions or to perform any preventive maintenance;
V. modifications;
VI. combination or use with any products, materials, processes, systems or other matter not
provided or authorized in writing by us;
VII. unauthorized repair;
VIII. normal wear and tear; or
IX. external causes such as accidents, abuse, or other actions or events beyond our reasonable
control.
APERA INSTRUMENTS (Europe) GmbH
Wilhelm-Muthmann-Str. 15
42329 Wuppertal Germany
Tel.: [phone]
Email: [email protected]
www.aperainst.de