YOKOGAWA DPharp EJXC40A, User Manual

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<Appendix1. Safety Instrumented Systems Installation>
A1-2
IM 01C25W05-01EN
Table A1.2 Proof Testing
Testing method Tools required Expected outcome Remarks
Functional test:
1. Follow all Management of Change
procedures to bypass logic solvers if
necessary.
2. Execute HART command to send value
to high alarm (21.5 mA) and verify that
current has reached this level.
3. Execute HART command to send value
to low alarm (3.6 mA) and verify that
current has reached this level.
4. Restore logic solvers operation and
verify.
• Handheld terminal
• Calibrated pressure
source
Proof Test Coverage
=68%
The output needs to be
monitored to assure that the
transmitter communicates
the correct signal.
Perform three point calibration along with
the functional test listed above.
A1.2.6 Repair and Replacement
If repair is to be performed with the process online
the transmitter will need to be bypassed during the
repair. The user should setup appropriate bypass
procedures.
In the unlikely event that the transmitter has a
failure, the failures that are detected should be
reported to Yokogawa.
When replacing the transmitter, the procedure in the
installation manual should be followed.
The personnel performing the repair or replacement
of the transmitter should have a sufficient skill level.
A1.2.7 Startup Time
The transmitter generates a valid signal within 10
second of power-on startup.
A1.2.8 Firmware Update
In case firmware updates are required, they
will be performed at factory. The replacement
responsibilities are then in place. The user will not
be required to perform any firmware updates.
A1.2.9 Reliability Data
The failure rate and failure mode are the following
values.
Device λ
SD
λ
SU
λ
DD
λ
DU
SFF
EJX DRS --- 161 977 95 92.4%
The transmitter is certified up to SIL2 for use
in a simplex (1oo1) configuration, depending
on the PFDavg calculation of the entire Safety
Instrumented Function.
The development process of the transmitter is
certified up to SIL3, allowing redundant use of
the transmitter up to this Safety Integrity Level,
depending the PFDavg calculation of the entire
Safety Instrumented Function.
When using the transmitter in a redundant
configuration, the use of a common cause factor
(β-factor) of 2% is suggested. (However, if the
redundant transmitters share an impulse line or if
clogging of the separate impulse lines is likely, a
common cause factor of 10% is suggested.)
Note that the failure rates of the impulse lines need
to be accounted for in the PFDavg calculation.