Created on 03/17/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 1 of 2
MODEL
PRDN
Electro-proportional, direct-acting, pressure reducing/relieving valve, high
pressure setting with no command
SERIES 1 / CAPACITY: 20 L/min. / CAVITY: T-11A
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 reducing mode, connecting port 2 to port 1 at a customer specified pressure setting. Increasing the current to
the coil will proportionally decrease 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 closed in the transition between reducing and
relieving resulting in very low consumption of oil.
TECHNICAL DATA
Maximum Operating Pressure 350 bar
Maximum Valve Leakage at 110 SUS (24 cSt) 41 cc/min.
Seal kit - Cartridge Buna: 990-511-007
Seal kit - Cartridge Viton: 990-511-006
PROPORTIONAL PERFORMANCE DATA
Hysteresis (with dither) 6%
Hysteresis with DC input <8%
Linearity (with dither) <2%
Repeatability (with dither) <2%
Recommended dither frequency 140 Hz
(X)CONTROL
X No Manual Override
(D)ADJUSTMENT RANGE
D 400 - 200 psi (14 - 28 bar)
B 1000 - 400 psi (28 - 70 bar)
E 200 - 100 psi (7 - 14 bar)
(N)SEAL MATERIAL
N Buna-N
V Viton
COIL *
No coil
212 DIN 43650 3 pin (Hirschman), 12 VDC
224 DIN 43650 3 pin (Hirschman), 24 VDC
712 Twin Lead, 12 VDC
724 Twin Lead, 24 VDC
912 Deutsch DT04-2P, 12 VDC
924 Deutsch DT04-2P, 24 VDC
* Additional coil options are available
snhy.com/
PRDN
Model Code Example: PRDNXDNCONFIGURATION OPTIONS
Created on 03/17/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 2 of 2
TECHNICAL FEATURES
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).
Leakage specified in Technical Data is out of port 3 with a supply pressure of 2000 psi (140 bar) and the valve set at mid range. This leakage is directly proportional
to pressure differential and inversely proportional to viscosity expressed in centistokes.
The transition from reducing to relieving is closed. The result is very low leakage. However, there is a transitional step increase in pressure between reducing and
relieving modes. This step equals about 5% of the high end of the adjustment range, independent of the valve setting.
For optimum performance, an amplifier with current sensing and adjustable dither should be used. Dither should be adjustable between 100 - 250 Hz.
Coils are interchangeable with Sun's other full flow, solenoid-operated valves and can be mounted on the tube in either direction.
With no electrical signal, the reduced pressure setting will default to the customer specified value. Increasing the command to the coil will proportionally reduce the
secondary pressure value.
Suitable for accumulator circuits since the absence of pilot control flow results in reduced secondary circuit leakage.
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.
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.
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.
PERFORMANCE CURVES
