Yokogawa FD20 Immersion Fitting - Manual (Page 17)

IM12B6K2-01E-E
17
4-4. Salt bridge
This reference electrode/salt bridge
combination allows the measurement of
pH and ORP (Redox) potentials with normal
electrodes in those cases when:
A. excessive contamination of the flow
diaphragm is expected. The flow of the
reference liquid through the diaphragm is
increased by pressurising the container.
Consequently, the contamination rate will
decrease.
B. the process to be measured cannot
stand contamination with KCI. The
salt bridge can be filled with several
electrolytes, e.g. KNO3.
C. measurement has to be performed at
pressures up to 10 bar and temperatures
up to 100 °C. As the container with
reference liquid can be pressurised.
FLOW TUBE (A)
Material
: glass
Flow diaphragm : ceramic, PTFE or sleeve
Connector
: Ryton R4
TUBING (B)
Material
: nylon
Diameter : 1/4” o.d.
Length : 2 mtr.
CONTAINER (C)
Container
: PVC, PVC (transparent)
Mounting set : Ryton R4
O-ring : silicone
Connection : nylon
Weight : approx. 300 g.
Mounting : wall mounting (support
with hole for screw M5)
Temperature/
pressure ratio
: max. 200 kPa
(2 bar) at 100°C
Parts and accessories
Order nr. Description
SB20-VC Salt bridge with ceramic junction
SB20-VP Salt bridge with porous PTFE
junction
SB20-VS Salt bridge with glass sleeve
junction
K1500DX 5m tubing for SB20
K1500BW flow tube for SB20-VC
K1500EE flow tube for SB20-VP
K1500EF flow tube for SB20-VS
Note: The reference electrode must be
ordered seperately.
4-5. Protection hose installation kit
The protection hose installation kit is for
protection of electrode cable and/or tubing
between fitting and converter, connecting
box, supply unit, etc. The hoses can be
mounted directly to the hose connections(s)
on top of each fitting. Clamps for fixing are
part of the installation kit.
Parts and accessories
Order nr. Description
K1500DN Protection hose kit 3 m
K1500DP Protection hose kit 5,5 m
K1500DQ Protection hose kit 10 m
K1500DR Protection hose kit 15 m
K1500DS Protection hose kit 20 m
REFERENCE
ELECTRODE
Fig. 4-6. Mounting the salt bridge