Patent ID: 8714176

Claim:
A compensator adapted to maintain liquid within a housing of subsea equipment close to a variable ambient pressure, the compensator comprising: a fluid compartment arranged to contain liquid wherein at least one of the walls defining the compartment is a movable member, which movable member moves in use to alter the volume of the compartment; and a protection system for the compensator, the protection system comprising: a detection mechanism for detecting when the volume of the fluid compartment is outside a predetermined acceptable limit; a valve arrangement mountable on at least one port that is in selective fluid communication with the fluid compartment; and an actuator, wherein the detection mechanism is coupled to the valve arrangement via the actuator, such that when the detection mechanism detects that the volume of the fluid compartment is outside the predetermined limit, the actuator causes the valve arrangement to change state and to alter the volume of the fluid compartment; wherein the actuator is configured such that the valve arrangement remains in one state for a predetermined period of time during volume changes in the compartment caused by movement of the movable member, prior to a further change in state of the valve arrangement.