#WishIknew: What is SIL in level transmitters?

Level System Integration

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I wish I knew what SIL is in level transmitters!

To find out what SIL means for a level transmitter, you need to know the meaning in the first place!

SIL stands for safety integrity level. This level tells you the amount of risk reduction a safety function gives you. It may also denote the probability of failure on demand (PFD) or the desired level of performance from a safety instrumented function (SIF). We have four SIL levels based on the IEC 610508 standard, with SIL 4 as the most trustworthy.

When you have a SIL solution in your plant, it needs appropriate equipment to work at its SIL level. And SIL certification means your level transmitter passed tests on the required constraints of critical and minimum failure.

These tables show you how the levels work within the IEC 610508 standard.

Courtesy of Wikipedia
  • PFD – probability of failure on demand
  • SIL – safety integrity level
  • RRF – risk reduction factor

For continuous operation:

Courtesy of Wikipedia
  • PFH – probability of failure per hour
  • SIL – safety integrity level
  • RRF – risk reduction factor

Hope that helps! If you need more, then please let us know!

Here are some articles related with level transmitters;

Level transmitter malfunction

Expert Answer : “We have the Endress+Hauser Levelflex FMP51 installed on a diesel tank for level measurement, but its output is not changing proportionally to the tank level. In the control room, we simulated different currents from the transmitter function menu and the transmitter responded fine. What do we need to fix?” For answer, click the article !

Capacitive level transmitter working principle

Expert Answer : “Where can I use the capacitive level transmitter? Can you tell me more about it and how I install it? For answer, click the article !”

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