NEVER Use B10 Values for PFDavg Calculations
Thursday, November 17, 2011Viewed 2626 times
The machine safety community has defined a number called the “B10 number.” It is a measure of time where 10% of a population of devices should have failed. Generally it is a measure of expected end of life or “useful life” as defined by the reliability engineering community.
The IEC/ISO 13849-1 functional safety standard for simple machines has defined equations directly relating the B10 number to the average random failure rate in the time period before end of life. For any given application, the cycle rate is estimated and the “random failure rate” is calculated. I heard one engineer state in an email “This is great. We finally are getting failure rate data from these safety relay companies.” Whoa! …
Failure Data • (0) Comments • Permalink