Abstract: A pressure reduction valve for a compressible fluid has an inlet and outlet separated by a pressure reduction member having a plurality of convergent-divergent nozzles High pressure gas or vapour passes from the valve inlet through the nozzles which control the expansion of the gas/vapour to a reduced pressure and eliminate shock waves. The gas/vapour expands into an intermediate attenuation chamber in which the resulting turbulence is confined before the gas/vapour passes through the diffuser into the outlet such that the diffused streams do not interact. The invention provides for pressure reduction with significantly reduced noise levels.

Abstract: A circuit for and method of controlling transient currents on power conductors includes a voltage-controlled switch connected between one of the power conductors and a load. A turn-on circuit is connected to the switch to control the switch during a transition period in which the switch changes from a non-current conducting state to a conducting state in which a static current flow to the load can be maintained. The turn-on circuit controls turn-on such that the rate of rise and the peak amplitude of the current through the switch is limited during the transition period. A reset circuit also is connected to the voltage-controlled switch to reset the switch to a non-conductive state when the voltage between the power conductors drops out. The reset circuit is configured to reset the switch within a reset period having a duration that is shorter than the duration of the transition period.