WPI APOLLO 4000, Instruction Manual

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APOLLO 4000
HYDROGEN PEROXIDE DETECTION
World Precision instruments e-5
Changing the Membrane Sleeve
All membrane sleeves replacing will eventually have to be done by the user. the
procedure for doing is simple and straightforward.
1.
unscrew the locking cap from the handle.
2.
Hold the stainless steel sleeve and remove it with the locking cap from the
internal electrode, being careful not to bend the electrode assembly when
doing so.
3.
rinse the internal electrode with distilled water (particularly the tip) and
let it soak for at least 5 minutes. Be careful not to let water get into the
handle. the current on the Apollo – 4000 should go offscale when the
electrode is being rinsed.
4.
Gently dry the electrode with a soft tissue (Kimwipes). Be sure to dry
thoroughly the flat surface at the tip of the electrode. After drying the
current should stabilize fairly quickly to a low value ( e.g., 0 - 0 pA). if this
occurs, then the electrode is in good working order.
5.
if the electrode is not clean, repeat steps 3 and 4. if necessary the iso-
noP rejuvenator (WPi #JuV) can be used to restore sensitivity of an old
electrode (contact WPi for assistance).
6.
remove the locking cap from the old used sleeve, and gently slide it onto
the new replacement sleeve.
7.
dip the internal electrode - cm into the electrolyte , the current should
go offscale during this. using the microFil™ non-metallic syringe needle
and ml plastic syringe, supplied, inject approximately 00 ul of
electrolyte directly into the new sleeve. the microFil supplied should be
less than the length of the sleeve, so that it will not puncture the delicate
membrane at the tip of the sleeve during injection. if the microFil is longer
than the sleeve it can be cut to the correct length.
8.
slowly and smoothly insert the electrode into the sleeve, and screw the
locking cap into the handle. the electrode should be observed to press
gently against the membrane.
9.
the current at this time will be high or offscale.