WPI STX2-PLUS, Инструкция по эксплуатации

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STX2-PLUS
World Precision Instruments 7
Testing the STX2-PLUS Electrodes
If another electrode is being used, refer to that electrode’s manual.
To make sure the electrode is operating properly, a resistance test in KCl is used. This
test demonstrates electrode functionality.
40 mM KCl 80 mM KCl 160 mM KCl
38-66 Ω 27–44 Ω 12–20 Ω
At the lower molarities (10–20 mM), a DMEM coated electrode will begin to show
instabilities at the higher concentrations. If the resistance readings in the KCl mixtures
are over 10% out of range, then the electrode may need cleaning. See “Cleaning/
Maintaining the STX2-PLUS Electrodes” on page 5. An Excel scatter plot of the
molarity vs. resistance (as a power) should show an R
2
value > 0.99x.
NOTE : These resistance readings can vary due to fluid volume and electrode depth.
These values are a reference. An Excel scatter plot of the molarity vs. resistance
(as a power) should show an R
2
value > 0.99x. If the R
2
value is acceptable, then the
electrode can be used even if it is slightly out of range. If the resistance readings in the
KCl mixtures are out of range, then the electrode may need cleaning. See “Cleaning/
Maintaining the STX2-PLUS Electrodes” on page 5. Electrodes which are not being
properly maintained may begin to show instabilities indicating the need for cleaning.
Regular maintenance of the electrode is strongly recommended for longevity.
ACCESSORIES
99675 EVOM2 Adaptor Cable
7363-4 Enzol Enzymatic Detergent
Fig. 10—Plug the STX2-PLUS into the 99675 cable to use the electrode with an EVOM2. The
99675 cable is sold separately.