You might try this:(L:Center Hydraulic Switch 1, enum) 1 == (L:Center Hydraulic Switch 2, enum) 1 == orif{ (L:Center hydraulic pressure, psi) 10 + 2970 min (>L:Center hydraulic pressure, psi) } els { (L:Center hydraulic pressure, psi) 10 - 0 max (>L:Center hydraulic pressure, psi) }After you make it work, you could try this little more complex that will add a bit of pressure when both switches are on, as per your desire :-)(L:Center Hydraulic Switch 1, enum) 1 == s0(L:Center Hydraulic Switch 2, enum) 1 == s1 or if{ (L:Center hydraulic pressure, psi) 10 + 2970 15 l0 l1 * * + min (>L:Center hydraulic pressure, psi) } els { (L:Center hydraulic pressure, psi) 10 - 0 max (>L:Center hydraulic pressure, psi) }TomPD: Be sure to check the proper spacing within the syntax.

Hi, 15 l0 l1 * * + is a good one!I add also some N2, Hz and Bleedair to give more "oscillation".Jan"Beatus ille qui procul negotiis..."

Jan,Actually oscillation occurs mostly by the use of flight controls (30-60 psi fluctuations). The redudancy in pumps make each system pretty stable, especially when both are working.Tom

Thanks for all the help, I manged to get it work how I want it to. The pressures are taken from the level D 767 panel, and work simliar to that panel, the only thing I have not modelled yet is the rotary switch.Here is the working valueAnd once again Thanks for all the help.Cheers(L:Center Hydraulic Switch 1, enum) 1 == if{ (L:Center Hydraulic Switch 2, enum) 0 == if{ (L:Center hydraulic pressure, psi) 10 + 2970 min (>L:Center hydraulic pressure, psi) } } els { (L:Center Hydraulic Switch 1, enum) 0 == if{ (L:Center Hydraulic Switch 2, enum) 1 == if{ (L:Center hydraulic pressure, psi) 10 + 2970 min (>L:Center hydraulic pressure, psi) } } els { (L:Center Hydraulic Switch 1, enum) 1 == if{ (L:Center Hydraulic Switch 2, enum) 1 == if{ (L:Center hydraulic pressure, psi) 10 + 3170 min (>L:Center hydraulic pressure, psi) } } els { (L:Center Hydraulic Switch 1, enum) 0 == if{ (L:Center Hydraulic Switch 2, enum) 0 == if{ (L:Center hydraulic pressure, psi) 10 - 0 max (>L:Center hydraulic pressure, psi) } }

"I manged to get it work how I want it to"Good. Most important is to use the code you feel more comfortable with. :-)"the only thing I have not modelled yet is the rotary switch." There ain't no rotary switchs for hydraulics in the 757.Proper documentation is of a great help in the development of a complex project. :-)Tom