Ionode IJ pH V5.1 - Manual (Page 20)

Ionode IJ Instruction Manual 20
4.4. Maintenance
1) When not in use, keep the electrode
immersed in 2-3M KCl (saturated KCl is
approx 4M). This assists in maintaining a
stable junction potential and is preferable to
deionised water or buffers.
2) pH membranes are NOT damaged if
allowed to dry. Ionode pH glasses re-
hydrate very quickly, typically in less than
an hour. Any impurities which have dried on
the membrane should be removed before
re-hydration (see 4.4.1
Cleaning ).
3) How often does the sleeve electrolyte need
replacing? This depends on the sample
being measured and is best determined by
experience. Error can be determined by
comparing readings before and after
renewal of the electrolyte on the same
sample. Normally, errors of less than a few
hundredths of a pH can be expected after a
full day's use and electrolyte need only
require weekly replacement.
4) For long term storage, remove and clean
the sleeve. Replace the sleeve without
electrolyte and attach the wetting cap, filled
with 20% KCl solution. After long term
storage algae or mould growth may occur
inside the wetting cap. This can be removed
by soaking in dilute chlorine (bleach)
solution.