Instruction manual

Instruction Manual PCD 650
108
7.4.3 Membrane Housing Replacement
Replacement of the membrane cap housing/ membrane is
required only when you cannot calibrate the probe, or if the
membrane is damaged.
Typical membrane damages are punctures or wrinkles caused
during measurements or cleaning.
Your new DO probe comes with replacement membrane housing.
To order more replacement membrane housing, see the
“Accessories” section page.
To replace the membrane cap (with pre-installed membrane)
1. Replacement is much easier with single membrane
housing. Unscrew the old membrane cap housing.
2. Hold the probe under hot running water and brush away
the white oxide on the cylindrical anode with a stiff plastic
brush – do not use metal cleaning material.
3. If the cathode has any deposits, remove them with a light
scouring powder. Do not polish the cathode.
4. Fill the new membrane cap housing with electrolyte
solution and inspect the bottom for leaks. If the solution
drops are leaking from the membrane, use new cap
housing.
5. If the assembly is leak-free, fill the membrane cap housing
with electrolyte to the brim.
6. Tap the side of the housing gently to remove any air
bubble that may be sticking to the membrane.
7. Screw the cap onto the probe. Excess electrolyte will
drain out.
8. Replace probe guard.
9. Calibrate the probe after the % saturation readings have
stabilised.
7.4.4 Membrane/O-ring Replacement (Optional Procedure)
It is recommended only experienced service personnel can
perform this procedure.
This procedure is OPTIONAL, and should only be performed if
you have new membrane and O-ring. You are also required to
have a membrane installation tool. These items are available
as optional accessories in the “Accessories” section.
Pull off the probe guard.
1. Unscrew the membrane cap from the probe.
Figure 91:
Positioning of O-ring
& membrane
Figure 92: Positioning
of O-ring & membrane