Frequently Asked Question
I would like to know how to model a SIF that doesn't have a logic solver, where the sensor is hardwired to the motor starter. I find that I have to pick a logic solver for the SIL verification to calculate my achieved SIL rating.
Last Updated 3 years ago
In exSILentia-SILver we want to make sure that we only conclude that the SIF achieves a SIL when the entire SIF is modelled. Hence we would like to see, sensor, logic solver, and final element modelled. In this case where you do not have a physical logic solver, you will need to "trick" exSILentia. For a scenario like this I define a user defined logic solver (see steps in attached PDF). Make sure that you select a calculation model (1oo1). Name the logic solver "wire" and use a LambdaSU of 1e-9 and a LambdaSU of 1e-11 (roughly the failure rates of a resistor). Next assign this wire as the logic solver in your SIF.