Parker Hannifin has added a D-version option to its direct-operated DFplus Gen IV valve range, introducing a second, freely configurable control loop for closed-loop hydraulic applications.
The new version allows analogue pressure or displacement sensors to be connected directly to the valve electronics, with sensor power supplied through the same electronics package. By integrating the feedback loop at valve level, Parker is reducing the external control hardware normally required for pressure, position, or volume-flow control in demanding hydraulic systems.
Applications identified by the company include pressure control in paper machines, rapid pressure control and relief in high-speed presses, volume-flow control in pumps, and highly precise pressure control in dynamic industrial processes. These are areas where hydraulic response, sensor resolution, and controller tuning have to be kept tightly aligned if machines are to maintain speed and repeatability under load.
The D-version combines DFplus pilot-valve performance with a high-resolution sensor signal interface and selectable setpoint type for analogue setpoint signals. Sensors connect through an M12 socket on the valve electronics, while configuration can be carried out using Parker ProPXD software or through an IO-Link connection.
Standard IO-Link Class A is supported, with an optional IO-Link Class B variant available where a switchable controller is required. The option is available for the D1FP, D3FP, and D30FP valve series, giving Parker a common control-loop extension across several direct-operated proportional DC valve sizes.
Hydraulic systems remain central to presses, machine tools, paper machinery, forming equipment, and industrial test rigs, but the surrounding control architecture is changing. More machines now require hydraulic components that can be commissioned, tuned, and diagnosed within connected automation environments, rather than treated as isolated mechanical subsystems.
Frank Henschke, Product Manager at Parker’s Hydraulic Valve Systems Division Europe, said: “The DFplus D-version valves offer a cost-effective solution for high dynamic closed loop-controlled applications such as volume flow control in pumps or highly precise pressure control in demanding applications”.
With the second loop built into the valve electronics, the DFplus D-version gives hydraulic control systems a more compact route to fast feedback and localised parameterisation. That reduces cabinet complexity and shortens the control path between sensor input, valve response, and machine behaviour — a practical gain where hydraulic axes have to react quickly without adding another layer of hardware.
Detailed technical data, configuration options, and local availability are available through Parker’s direct-operated proportional DC valve product page.
