Yokogawa EJA530A - Manual (Page 54)

IM 01C21F01-01E 9-5
9. MAINTENANCE
9.4.3 Cleaning and Replacing the
Capsule Assembly
This subsection describes the procedures for cleaning
and replacing the capsule assembly. (See Figure 9.4.3.)
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 re-
placed.
• 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 Allen screws 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 and dry
thoroughly after cleaning.
1) Remove the CPU assembly as shown in Subsection
9.4.2.
2) Remove the two Allen screws and the pipe (shown
in Figure 9.4.3) for the model EJA530A with
Measurement span code A, B, and C, which connect
the transmitter section and capsule assembly.
3) Separate the transmitter section and capsule assem-
bly.
4) Clean the capsule assembly or replace with a new
one.
᭿ Reassembling the Capsule Assembly
1) Insert the capsule assembly to the transmitter
section. For the model EJA530A with Measurement
span code A, B, and C with the pipe (shown in
Figure 9.4.3), insert the capsule assembly in a way
that the direction of the pipe screw thread matches
to that of the zero-adjustment screw of the transmit-
ter section.
2) Tighten the two Allen screws to a torque of 5 N·m
and the pipe with gasket if applied.
3) Install the CPU assembly according to Subsection
9.4.2.
4) After completing reassembly, adjust the zero point
and check the parameters.
F0904.EPS
Transmitter section
Capsule assembly
Capsule name plate
Pipe screw thread
Zero-adjustment
screw
Pipe
Allen screw
Allen screw
Gasket
Figure 9.4.3 Removing and Mounting the Capsule
Assembly