4.5:1 pilot ratio, standard capacity counterbalance valve assembly


Port Headings and Sizes [ + ]
Modifiers Ports
X4F, /10, /11, /S, /S3 Port 1: 3/8" BSPP; Port 2: 3/8" BSPP; Port 3: 1/4" BSPP;
Cartridge Technical Features [ + ]

Counterbalance valves with pilot assist are meant to control an overrunning load. The check valve allows free flow from the directional valve (port 2) to the load (port 1) while a direct-acting, pilot-assisted relief valve controls flow from port 1 to port 2. Pilot assist at port 3 lowers the effective setting of the relief valve at a rate determined by the pilot ratio.

Other names for this valve include motion control valve and over-center valve.

  • Counterbalance valves should be set at least 1.3 times the maximum load induced pressure.
  • Turn adjustment clockwise to decrease setting and release load.
  • Full clockwise setting is less than 200 psi (14 bar).
  • Backpressure at port 2 adds to the effective relief setting at a ratio of 1 plus the pilot ratio times the backpressure.
  • Reseat exceeds 85% of set pressure when the valve is standard set. Settings lower than the standard set pressure may result in lower reseat percentages.
  • Sun counterbalance cartridges can be installed directly into a cavity machined in an actuator housing for added protection and improved stiffness in the circuit.
  • Two check valve cracking pressures are available. Use the 25 psi (1,7 bar) check unless actuator cavitation is a concern.
  • This valve does not have positive seals on the pilot section and will pass up to 3 in³/min.@1000 psi (45 ml/min.@70 bar ) between port 2 and port 3. This is a consideration in master-slave circuits and in the leak testing of valve-cylinder assemblies.
  • 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.
  • All 3-port counterbalance, load control, and pilot-to-open check cartridges are physically interchangeable (i.e. same flow path, same cavity for a given frame size).
  • Corrosion resistant cartridge valves are intended for use in corrosive environments and are identified by the model code suffix /AP for external stainless steel components, or /LH for external zinc-nickel plated components. See the CONFIGURATION section for all options. For further details, please see the Materials of Construction page located under TECH RESOURCES.
  • 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.
Cartridge Technical Data [ + ]
Note: Data may vary by configuration. See CONFIGURATION section.
Cavity T-11A
Series 1
Capacity 15 gpm60 L/min.
Pilot Ratio 4.5:14.5:1
Maximum Recommended Load Pressure at Maximum Setting 3850 psi270 bar
Maximum Setting 5000 psi350 bar
Factory Pressure Settings Established at 2 in³/min.30 cc/min.
Maximum Valve Leakage at Reseat 5 drops/min.0,3 cc/min.
Adjustment - No. of CCW Turns from Min. to Max. Setting 3.753.75
Operating Characteristic StandardStandard
Reseat >85% of setting>85% of setting
Valve Hex Size 7/8 in.22,2 mm
Valve Installation Torque 30 - 35 lbf ft41 - 47 Nm
Adjustment Screw Internal Hex Size 5/32 in.4 mm
Locknut Hex Size 9/16 in.15 mm
Locknut Torque 80 - 90 lbf in.9 - 10 Nm
Model Weight .40 lb0,20 kg
Seal kit - Cartridge Buna: 990011007
Seal kit - Cartridge EPDM: 990011014
Seal kit - Cartridge Polyurethane: 990011002
Seal kit - Cartridge Viton: 990011006
Manifold Technical Data [ + ]
Body Type Line mountLine mount
Interface Banjo BoltBanjo Bolt
Body Features Direct mountDirect mount
Banjo Bolt Installation Torque 53 lb. ft. to 58 lb. ft. (70 Nm to 77 Nm)53 lb. ft. to 58 lb. ft. (70 Nm to 77 Nm)
Banjo Bolt Hex .94.94
Open Cavities 11
Cavity T-11A
Port Size 3/8" BSPP3/8" BSPP
CAD Files [ + ]
Notes [ + ]
  • A fixed setting version is available for this model. To view this product page, use Sun's search box and type in the 4 letter model code. The search result will include the fixed setting version.
  • Important: Carefully consider the maximum system pressure. The pressure rating of the manifold is dependent on the manifold material, with the port type/size a secondary consideration. Manifolds constructed of aluminum are not rated for pressures higher than 3000 psi (210 bar), regardless of the port type/size specified.
Additional Resources [ + ]