Yokogawa EJA310A - Manual (Page 57)

IM 01C21D01-01E 9-6
9. MAINTENANCE
F0904.EPS
Transmitter section
Pressure-detector section
Cover flange
Capsule gasket
Flange bolt
Allen screw
Nut
Figure 9.4.3 Removing and Mounting the Pressure-
detector Section
9.4.4 Replacing the Process Connector
Gaskets
This subsection describes process connector gasket
replacement. (See Figure 9.4.4.)
(a) Loosen the two bolts, and remove the process
connectors.
(b) Replace the process connector gaskets.
(c) Remount the process connectors. Tighten the bolts
securely and uniformly to a torque shown below,
and verify that there are no pressure leaks.
Model EJA310A EJA430A
C capsule D capsule
EJA440A
Torque(N·m)
39 to 49 {4 to 5}
49 to 59
{kgf·m} {5 to 6}
F0905.EPS
Bolt
Process connector
Process connector gasket
Figure 9.4.4 Removing and Mounting the Process
Connector
9.5 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.
9.5.1 Basic Troubleshooting
First determine whether the process variable is actually
abnormal or a problem exists in the measurement
system.
If the problem is in the measurement system, isolate
the problem and decide what corrective action to take.
This transmitter is equipped with a self-diagnostic
function which will be useful in troubleshooting; see
Section 8.5 for information on using this function.
Abnormalities appear in measurement.
: Areas where self-diagnostic offers support
Is process variable
itself abnormal?
Inspect the
process system.
Isolate problem in
measurement system.
Does problem exist in
receiving instrument?
Check/correct
environmental conditions.
Inspect receiver.
Check transmitter.
Check/correct operating
conditions.
Measurement system problem
F0906.EPS
YES
NO
NO
YES
Environmental conditions
Operating conditions
Transmitter itself
Figure 9.5.1 Basic Flow and Self-Diagnostics