< Mentor Note -- thread moved to HH from the technical engineering forums, so no HH Template is shown > Hi, I am struggling with a couple of questions and would like to check my working so far. Question 6: To explain the operation: I believe the electric motor turns the pump which draws hydraulic fluid into the system through component F (which one depends on the direction of the pump). This creates a flow, turning the hydraulic motor. Because the pump and motor can only accept a certain flow, as more fluid is drawn into the system pressure will build, causing Components B&C to open in turn. The fluid will leave the system through the variable restriction, but only at a rate which maintains the required pressure in the system. Is this a correct interpretation of the circuit? I am not sure how to explain Question 6 part c) regarding the limitations of speed control - can anyone help? I would say that because the Pressure Relief Valves will be opening and closing, it would cause a fluctuation in the speed at A? Question 7: I am struggling to know where to start on this question, any guidance would be appreciated. Thanks Pete.