A modular relief valve is a sandwich plate that sits between the subplate and the directional valve. It limits pressure on one port without a separate valve, extra ports or extra hoses.

Which port?

P to T caps the whole station — the usual choice for a single function fed from a shared manifold. A to T or B to T caps one side of the actuator only, which is how you protect a cylinder that can be over-pressured in one direction while leaving the other at full system pressure.

Also available: DY-02-W-21 and DY-02-W-31.5 relieve both A and B to tank from one plate (210 bar and 315 bar), and VLP40DFC302A / VLP40DIFC302A give A&B-to-T and crossline relief at 250 bar / 40 L/min.

Modular valves stack. Each plate you add makes the assembly taller, so the mounting bolts must be longer — the bolt length in the table is what that single plate adds. Add up your stack and order the matching SHCS bolt set; they are not included.

Technicians Advice

Sandwich order matters: a relief module on P protects everything downstream of it in the stack, so put it closest to the manifold. Use longer stack bolts (one size up per module) and torque evenly or the O-ring faces weep. Set against a gauge on the P gauge point - and if you need relief on both work ports of a motor, that is a crossline relief module, not two singles.

Typical applications: System over-pressure protection for gear pumps, power packs and log splitters. Protecting a hydraulic motor circuit? See our crossline relief valves.