Which has a higher safety level, 1oo2 or 2oo3?
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This post was last edited by liu530014416 on 2022-12-19 at 11:24. Dear teachers, there is a pipeline in the field with two electromagnetic flowmeters connected in series; one of these flowmeters occasionally reaches the interlock value. The management has requested that another flowmeter be added, so that the interlock setting changes from 2-out-of-3 to 3-out-of-2. Question: Is this approach feasible? The safety level of this SIF circuit is SIL2; will it decrease if the interlock setting is changed to 3-out-of-2?
. No problem. As long as a single transmitter achieves SIL1, 2oo3 can achieve SIL3. Changing 1oo2 to 2oo3 reduces security, but improves availability. Changing 1oo2 to 2oo3 reduces safety levels somewhat, but it still meets the requirements of chemical production. Sensor structure safety: 1oo2＞2oo3＞1oo1＞2oo2. Sensor structure process availability: 2oo2＞2oo3＞1oo1＞1oo2.