Frequently Asked Question
When installing solenoids, does exSILentia assume 1 x solenoid per actuator & valve? Could a 1oo2 solenoid system for example be installed, or a common solenoid that closes two valves?
Last Updated 5 years ago
exSILentia does have Generic 1oo2 solenoid selection options in the SERH database. However, if you have specific solenoids you will need to specify a user defined device representing the 1oo2 solenoid configuration. In order get the equivalent failure rates of the 1oo2 configuration you would have to model an intermediate safety function with just the 1oo2 voting. Set the Mission Time to the Proof Test Interval, and set the Demand Mode to High. The resulting PFH is the equivalent Dangerous Undetected failure rate of the 1oo2 solenoid configuration, the MTTFS can be used to determine equivalent Safe Undetected failure rate (SU = 1/(MTTFS*8760)). You can use this method to model the one solenoid/two valves configuration as well.