Patent ID: 7000693

Claim:
Apparatus for use in controlling the operation of a hydrocarbon production well, comprising: supply means for providing an electric power supply a plurality of electrically operated actuating devices; a first drive means responsive to said power supply for providing a drive signal for said actuating devices; control means for multiplexing said drive signal and applying said multiplexed drive signal to said actuating devices; a second drive means, the control means being adapted to select whether to apply the drive signal of the second drive means to said actuating devices in a multiplexed manner or the drive signal from the first drive means to said actuating devices in a multiplexed manner; and wherein said control means causes the drive signal of the non-selected drive means of the first and second drive means instead of that of the selected drive means of the first and second drive means to be applied to said actuating devices in a multiplexed manner in the event of a fault.