Direct-acting relief valve - pilot capacity

Capacity: .5 gpm2 L/min. | Cavity: T-3A
RBAA : Direct-acting relief valve - pilot capacity
Technical Features [ + ]

Direct-acting, pilot relief cartridges are used to remotely control the pressure setting of other pilot-operated valves. Because capacity is limited to pilot flow, these valves should be used with other higher flow valves.

  • Main stage orifice is protected by a 150 micron stainless steel screen.
  • Suitable for use in load holding applications.
  • Back pressure on the tank port (port 2) is directly additive to the valve setting at a 1:1 ratio.
  • 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.
  • W and Y controls (where applicable) can be specified with or without a special setting. When no special setting is specified, the valve is adjustable throughout its full range using the W or Y control. When a special setting is specified, this setting represents the maximum setting of the valve.
  • 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.
Technical Data [ + ]
Cavity T-3A
Series 2
Capacity .5 gpm2 L/min.
Maximum Operating Pressure 5000 psi350 bar
Response Time - Typical 2 ms2 ms
Maximum Valve Leakage at 110 SUS (24 cSt) 5 drops/min.0,3 cc/min.
Adjustment - Number of Clockwise Turns to Increase Setting 55
Valve Hex Size 1 1/8 in.28,6 mm
Valve Installation Torque 45 - 50 lbf ft61 - 68 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 .50 lb0,25 kg
Seal kit - Cartridge Buna: 990203007
Seal kit - Cartridge EPDM: 990203014
Seal kit - Cartridge Polyurethane: 990003002
Seal kit - Cartridge Viton: 990203006
Performance Curves [ + ]
FAQs [ + ]

Pressure setting tolerances are listed in our Performance Data page. A link to this page can also be found in the Additional Resources tab of the applicable product page.

There are exactly 250 Sun drops in a cubic inch or 15 in a cc.

Maybe not. We build in a good amount of overlap in the kick-down reliefs to prevent false tripping. This means they are not as fast as our standard pilot-operated reliefs. A direct-acting relief valve set just above the kick-down relief valve would be good insurance.

Direct-acting valves are used to prevent over pressure, and pilot-operated valves are used to regulate pressure. If you are unsure, use a direct-acting valve. Sun's direct acting valves are very fast, dirt tolerant, stable, and robust. Sun's pilot-operated valves are moderately fast, they have a low pressure rise vs. flow curve, and they are easy to adjust.

One graphic example is on a portable grain auger for silos. When the farmer gets caught in the auger the kick-down relief trips and allows him to escape.

Notes [ + ]
  • For Series 2 cartridges configured with an O control (panel mount handknob), a 1.00 in. (25,4 mm) diameter hole is required in the panel.
Additional Resources [ + ]