Abstract: A trip oil system automatically controls the fuel shut-off valves in an industrial gas turbine. The trip oil system applies hydraulic pressure to actuate and hold open a fuel shut-off valve so that fuel flows to the combustor of the gas turbine. When the trip oil system relieves the hydraulic pressure, the fuel shut-off valve closes and stops the fuel flow to the combustor. A bank of three solenoid valves controls the application of hydraulic pressure to each fuel shut-off valve. Hydraulic fluid conduits interconnect the three solenoid valves such that no single valve by itself can relieve the hydraulic pressure applied to the fuel shut-off valve. During normal operation of the gas turbine, all three redundant solenoid valves are activated. For the trip oil system to cause the fuel shut-off valve to close, at least two of the solenoid valves must de-energize to relieve pressure to the fuel shut-off valve.