Model

PRDLLMXDN

M-Control
Control
Operating Range
Seal Material
Coil

Model: PRDL

Electro-proportional, direct-acting, pressure reducing/relieving valve with open transition

Cavity: T-11A | Capacity:

Model

PRDLLMXDN

M-Control
Control
Operating Range
Seal Material
Coil

Technical specifications

This electro-proportional, direct-acting reducer/reliever valve reduces a high primary pressure at the inlet (port 2) to a constant reduced pressure at port 1, with a full flow relief function from port 1 to tank (port 3). The valve is biased to the relieving mode. Energizing the coil connects port 2 to port 1. Increasing the current to the coil will proportionally increase the reduced pressure at port 1. If pressure at port 1 exceeds the setting induced by the coil, pressure at port 1 is relieved to port 3. This valve is open in the transition from reducing to relieving. It provides good pressure control and dynamic response. Optional full manual control is available.

  • Maximum pressure at port 3 should be limited to 3000 psi (210 bar).
  • Pressure at port 3 is directly additive to the valve setting at a 1:1 ratio and should not exceed 3000 psi (210 bar).
  • The transition from reducing to relieving is slightly open. The result is very good pressure control with oil consumption of about 0.1 gpm (0,4 L/min.).
  • For optimum performance, an amplifier with current sensing and adjustable dither should be used. Dither should be adjustable between 100 - 250 Hz.
  • Full reverse flow from reduced pressure (port 1) to inlet (port 2) may cause the main spool to close. If reverse free flow is required in the circuit, consider adding a separate check valve to the circuit.
  • Direct acting concept provides highly reliable operation in contaminated systems, especially at dead headed conditions.
  • All three-port pressure reducing and reducing/relieving cartridges are physically interchangeable (i.e. same flow path, same cavity for a given frame size). When considering mounting configurations, it is sometimes recommended that a full capacity return line (port 3) be used with reducing/relieving cartridges.
  • NOTE: There is no upper limit to the pressure setting when using the M control. The more force you exert on the manual override, the higher the resulting pressure.
  • The 'E' manual control assembly has a mechanical life expectancy of approximately 7,000 cycles.
  • The momentary/twist override option "E" allows the operator to shift the valve by twisting the manual override clockwise 90 degrees.
  • Cartridges configured with EPDM seals are for use in systems with phosphate ester fluids. Exposure to petroleum based fluids, greases and lubricants will damage the seals.
  • Uses for the 'L' manual screw adjustment include: emergency valve setting during power failure or alternatively boosting the valve setting
  • With the 'L' adjustment screw, all ranges are factory set at zero (adjustment screw fully backed out). With the coil de-energized, clockwise adjustment of the screw will increase the spring bias load up to the maximum setting for that range. With the coil energized, any mechanical pressure setting is directly additive to the coil induced value.
  • Incorporates the Sun floating style construction to minimize the possibility of internal parts binding due to excessive installation torque and/or cavity/cartridge machining variations.
  • Hysteresis (with dither)
    6%
  • Hysteresis with DC input
    <8%
  • Linearity (with dither)
    <2%
  • Repeatability (with dither)
    <2%
  • Recommended dither frequency
    140 Hz
  • Hysteresis (with dither)
    6%
  • Hysteresis with DC input
    <8%
  • Linearity (with dither)
    <2%
  • Repeatability (with dither)
    <2%
  • Recommended dither frequency
    140 Hz

Model CAD Files

Files not yet avialable. Click below to request them.

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