Emerson El-O-Matic E Series - Section 5: Failure Modes and Estimated Failure Rates

Failure Modes and Estimated Failure Rates
Section 5: Failure Modes and Estimated
Failure Rates
Table 1� Failure Rates – EL-O-Matic E-Serie Pneumatic Actuator
Failure Category
Failure Rate (in FIT)
Spring-Return Double-Acting
Fail Safe 76 0
Fail Dangerous Undetected 342 362
No Effect 1550 1285
Table 2� Failure Rates – EL-O-Matic P-Serie Pneumatic Actuator
Failure Category
Failure Rate (in FIT)
Spring-Return Double-Acting
Fail Safe 80 0
Fail Dangerous Undetected 559 465
No Effect 1993 1265
The failure rates for the EL-O-Matic E and P Series pneumatic actuator when performing
partial valve stroke testing are listed in the table below:
Table 3� Failure Rates – EL-O-Matic E-Serie Pneumatic Actuator with partial valve stroke testing
Failure Category
Failure Rate (in FIT)
Spring-Return Double-Acting
Fail Safe
76 0
Fail Dangerous Detected
225 201
Fail Dangerous Undetected
117 161
No Effect
1550 1285
Table 4� Failure Rates – EL-O-Matic P-Serie Pneumatic Actuator with partial valve stroke testing
Failure Category
Failure Rate (in FIT)
Spring-Return Double-Acting
Fail Safe 80 0
Fail Dangerous Detected 370 256
Fail Dangerous Undetected 189 209
No Effect 1993 1265
NOTICE
No internal diagnostics is included in the device. These values are valid when taken in
account the maintenance interval and procedure described in Section 7, and for the
expected lifetime dened in Section 4.
SIL Safety Manual
DOC.SILM.EEP.EN Rev. 0
April 2017
6
Section 5: Failure Modes and Estimated Failure Rates