Question 69
CEL01A hydraulic system flow control circuit is shown in the illustration and is known as a __________. Illustration GS-0105

AI Explanation
The Correct Answer is B
**Why option B ("metered-in circuit") is correct:**
A metered-in circuit is characterized by placing the flow control valve (FCV) on the **inlet** side of the actuator (like a hydraulic cylinder or motor). This configuration controls the rate at which fluid enters the cylinder, thereby controlling the speed of the actuator during the working stroke (extension in the case of a cylinder). In the illustrated circuit (GS-0105), the flow control device is positioned directly before the cylinder's piston port, regulating the flow **into** the cylinder, which defines it as a metered-in circuit.
**Why the other options are incorrect:**
* **A) bleed-in circuit:** This term is not standard nomenclature for controlling actuator speed in hydraulic systems. Speed control is achieved using metered-in, metered-out, or bleed-off configurations.
* **C) bleed-off circuit:** A bleed-off (or bypass) circuit controls speed by diverting (bleeding) a portion of the pump flow directly back to the tank **before** the fluid reaches the actuator, thus reducing the effective flow supplied to the cylinder. The flow control valve in a bleed-off circuit is typically placed in a parallel line between the pressure line and the tank, not directly in series with the actuator's inlet.
* **D) metered-out circuit:** A metered-out circuit controls the speed by placing the flow control valve on the **outlet (exhaust)** side of the actuator. This controls the rate at which fluid leaves the cylinder, thereby controlling the actuator speed. Since the illustrated FCV is on the inlet side, this option is incorrect.
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