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<8. Maintenance>
8-5
IM 01C25F01-01E
8
.4.3 Cleaning and Replacing the Capsule
Assembly
This subsection describes the procedures for
cleaning and replacing the capsule assembly. (See
figure 8.4.)
CAUTION
Cautions for Flameproof Type Transmitters
Users are prohibited by law from modifying the
construction of a flameproof type transmitter. If
you wish to replace the capsule assembly with
one of a different measurement range, contact
Yokogawa.
The user is permitted, however, to replace a
capsule assembly with another of the same
measurement range. When doing so, be sure to
observe the following.
• The replacement capsule assembly must
have the same part number as the one being
replaced.
• The section connecting the transmitter and
capsule assembly is a critical element in
preservation of flameproof performance, and
must be checked to verify that it is free of
dents, scratches, and other defects.
• After completing maintenance, be sure to
securely tighten the setscrews that fasten the
transmitter section and pressure-detector
section together.
■ Removing the Capsule Assembly
IMPORTANT
Exercise care as follows when cleaning the
capsule assembly.
• Handle the capsule assembly with care, and
be especially careful not to damage or distort
the diaphragms that contact the process
fluid.
• Do not use a chlorinated or acidic solution for
cleaning.
• Rinse thoroughly with clean water after
cleaning.
1) Remove the CPU assembly as shown in
subsection 8.4.2.
2) Remove the two setscrews that connect the
transmitter section and pressure-detector
section.
3) Remove the hexagon-head screw and the
stopper.
4) Separate the transmitter section and capsule
assembly.
5) Clean the capsule assembly or replace with a
new one.
■ Reassembling the Capsule Assembly
1) Insert the capsule assembly to the transmitter
section. Reattach the sopper with the hexagon-
head screw.
2) Tighten the two setscrews. (Tighten the screws
to a torque of 1.5 N·m)
3) Install the CPU assembly according to
subsection 8.4.2.
4) After completing reassembly, adjust the zero
point and recheck the parameters.
F0804.ai
Transmitter section
Capsule assembly
Setscrew
Stopper
Hexagon
head screw
Figure 8.4
Removing and Mounting the Pressure-
detector Section
8.5 Troubleshooting
If any abnormality appears in the measured values,
use the troubleshooting flow chart below to isolate
and remedy the problem. Since some problems
have complex causes, these flow charts may
not identify all. If you have difficulty isolating or
correcting a problem, contact Yokogawa service
personnel.