* Example for n=2;  units are different 

bind 
MTTF1 1/(10*(10^4))
MTTR1 1/(1.25*(10^8)) 
MTTF2 1/(20*(10^4))
MTTR1 1/(2.5*(10^8))
n 2
end

block rbd1  
comp Unit1 ss_unavail(1/MTTF1, 1/MTTR1)
comp Unit2 ss_unavail(1/MTTF1, 1/MTTR2)
series sysX Unit1 Unit2
end


* variable named U is the  system steady-state unavailability 
var U sysprob(rbd1)

* variable named downtime is the system downtime in minutes per year
var downtime 60*8760*U

* variable named A is the system steady-state availability
var A 1-U

* Mean Time To System Failure
var MTTSF 1/(1/MTTF1+1/MTTF2)

* Mean Time To System Restoration
var MTTSR   U*MTTSF/A 

expr  A, U,downtime, MTTSF, MTTSR
end
