Hydraulic accumulator as leakage compensator
In this application (Figure 7.23), the accumulator acts as a compensator, by compensating for losses due to internal or external leakage that might occur during an extended period of time, when the system is pressurized, but not in operation.
The pump charges the accumulator and the system, until the maximum pressure setting on the pressure switch is obtained. When the system is not operating, it is required to maintain the required pressure setting, to accomplish which the accumulator supplies leakage oil to the system during a lengthy period of time. Finally when the system pressure falls below the minimum required pressure setting, the pump starts to automatically recharge the system. This saves electrical power and reduces heat in the system.