Krohne OPTISWITCH 3x00C Contactless SIL EN User Manual

Safety ManualOPTISWITCH series 3000- contactless electronic switch

The chronological sequence of PFDavgis nearly linear to theoperating time over a period up to 10 years. The above valuesapply only to the TProofinterv

OPTISWITCH series 3000 • - contactless electronic switch 11Functional safety32741-EN-080414

Subject to change without notice32741-EN-080414

Content1 Functional safety1.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31.2 Planning . . . . . . . . . . . . . . . . . . . .

1 Functional safety1.1 GeneralThis safety manual applies to measuring systems consisting ofthe vibrating level switch OPTISWITCH series 3000 withinteg

FIT Failure In Time (1 FIT = 1 failure/109h)MTBF Mean Time Between FailureMTTF Mean Time To FailureMTTR Mean Time To Repairl IEC 61508 (also available

The safe state depends on the mode:Overflow protection(max. operation)Dry run protection(min. operation)Vibrating element in safestatecovered uncovered

Number values see chapter "Safety-related characteristics".If the "low demand rate" does not apply, the measuring systemas safety-

l Avoid buildup on the vibrating system (probably shorterproof test intervals will be necessary)l Fork version: avoid granulate size of the medium >

1.6 Recurring function testThe recurring function test is used to check the safety function,to detect possible non-recognisable, dangerous faults. The

For a higher average temperature of 60 °C (140 °F), the failurerates should be multiplied by a factor of 2.5. A similar factorapplies if frequent temp