Taiwan SHAKO PU520-02-S 5/2-Way Solenoid Valve

Not SMC, it is a 5/2-way solenoid valve manufactured by Taiwan SHAKO. Often mislabeled as SMC in the market.

PU520-02-S Technical Specifications

Valve type: 5/2-way, single solenoid, spring return

Actuation: Internal pilot operated

Ports: P/A/B ports G1/4 (02), R/S exhaust ports G1/8

Effective cross-sectional area: 18 mm²

Operating pressure: 0.15-0.8 MPa (1.5-8 kgf/cm²)

Proof pressure: 0.99 MPa

Media: Compressed air, filtration accuracy 40 μm, oil-free lubrication acceptable

Ambient temperature: -10～+50℃

Protection class: IP65; Insulation class F

Duty cycle: 100% continuous operation

Valve body: Anodized aluminum alloy; Weight approx. 270 g

Manual override: Lockable manual button

Standard coil voltages: DC24V, AC110V, AC220V; other voltages optional

Model Decoding

Alternative Selection

1. SMC equivalent reference: SY5120-02 (G1/4, 5/2-way single solenoid, internal pilot)
2. Domestic alternative: 4V310-08 (G1/4, comparable flow capacity)

Application Notes

1. Minimum supply pressure for internal pilot version is 0.15 MPa. It will fail to shift below this pressure. For low-pressure conditions use external-pilot type PU520A-02-S.
2. Coil uses DIN socket. Provide waterproof protection for outdoor installation.
3. Manual override: Press to lock, rotate to release, used for cylinder commissioning without power supply.

Operating Principle of SHAKO PU520-02-S (Internal Pilot 5/2-Way Single Solenoid Valve)

Assembly consists of two parts: Upper pilot assembly (coil + small pilot spool) + Main spool assembly (main spool + return spring).

The coil only drives a small pilot valve. The main spool is not driven directly by electromagnetic force; it is actuated by air pressure differential. Internal-pilot design requires supply pressure ≥0.15 MPa for proper shifting.

Port Definition

P: Air supply inlet (G1/4)

A, B: Connect to two chambers of double-acting cylinder

R, S: Exhaust ports, normally fitted with silencers

1. Coil de-energized (Normal state, spring return)

Return spring pushes main spool to home position.

Air circuit path:

P → B supply air; A → R exhaust

Compressed air outputs from port B to one side of cylinder; air from opposite cylinder chamber exhausts through port A to atmosphere. Cylinder stays retracted / home position.

2. Coil energized (Shift action)
3. Coil energized, electromagnetic force pulls pilot armature, opens small internal pilot passage.
4. Supply air from port P flows through internal passages to control end of main spool.
5. Air pressure overcomes return spring force and shifts main spool assembly.
6. Main air circuit switches: P → A supply air; B → S exhaust.

Port A outputs compressed air to extend cylinder; exhaust air from cylinder opposite side discharges via port B through S port.

3. Coil de-energized, automatic reset

Electromagnetic force disappears, pilot spool resets and cuts pilot air supply.

Main spool returns to original position under return spring force. Air circuit reverts to de-energized state, cylinder automatically returns to home position.

⚠️ Key Points

1. Internal pilot relies on supply air pressure. No valve shifting below 0.15 MPa. For low-pressure scenarios select PU520A-02-S (external-pilot version with separate control air supply).
2. -S single solenoid: spring return on power loss. -D double solenoid: no return spring; maintains position upon power loss, requires opposite coil energization for reversal.
3. Manual override: press and lock for forced shifting; rotate to release. Used for cylinder test without power.

Difference from Direct-Acting Solenoid Valves

Direct-acting: Coil pushes main spool mechanically. Higher power consumption, lower flow rate, works at zero pressure.

PU520 internal pilot: Low coil power, supports 100% continuous duty, high flow capacity, minimum operating air pressure required.

Application Scenarios of SHAKO PU520-02-S

Core characteristics: Internal-pilot 5/2-way single solenoid valve, G1/4 port, drives double-acting cylinder, spring return when coil de-energized; minimum supply pressure ≥0.15 MPa.

Typical functions: Cylinder extend-retract reciprocation; pneumatic gripper opening/closing, stopper, lifting, pushing, clamping actions.

Machinery Industry Applications

1. Packaging Machinery

Vertical / horizontal packaging machines, case sealers, heat-sealing machines, bagging machines

Actions: Pushing material, material stopping, bag clamping, cutter cylinder, lifting stations

Features: Medium flow capacity, continuous energization, PLC-controlled cylinder reciprocation, widely used in packaging equipment.

2. Automation Conveyors & Assembly Equipment

Assembly jigs, transfer machines, sorting stations, conveyor stoppers

Actions: Stopper cylinders, lifting cylinders, push cylinders, simple fixtures

-S single-solenoid advantage: Automatic reset when signal drops; cylinder returns to safe position during fault conditions; saves PLC output points.

3. Rubber-Plastic & Injection Molding Auxiliary Equipment

Injection machine peripherals: grippers, door actuation, ejector mechanisms; extruder cutting units

Rubber machinery, compression molding pneumatic clamping, hopper gate actuation

4. Woodworking Machinery

CNC routers, edge banding machines: workpiece clamping, material pushing, stopping, positioning cylinders.

5. Printing & Textile Machinery

Printing press paper hold-down; textile machine pneumatic clamping, swing link reciprocating mechanisms.

6. Food Machinery

Simple filling equipment, material sorting, pneumatic baffles.

Note: Standard anodized aluminum body, not for direct contact with food media; only controls clean compressed air.

General Tooling & Special-Purpose Machines

1. Pneumatic fixture jigs: Welding fixtures, test jigs; workpiece clamping, auto-release upon power failure.
2. Machine-tool pneumatic systems: Pneumatic chucks, safety doors, protective gate cylinders.
3. Material handling: Hopper dampers, flip gates, discharge mechanisms.

Unsuitable Working Conditions (Selection Pitfalls)

1. Supply pressure persistently below 0.15 MPa: Internal-pilot cannot shift. Use PU520A-02-S external-pilot variant.
2. Position retention required after power loss: Do not use -S single solenoid; select -D double-solenoid with latching spool.
3. Zero-pressure start, vacuum circuits: Not applicable.
4. Heavy-corrosion, exposed outdoor environments: Add coil protective cover; bare installation not recommended.
5. Explosive-hazard areas: Order E1 explosion-proof coil version.

Compatible Actuators & Accessories

Suitable cylinder bore: Φ32-Φ80 double-acting cylinders (G1/4 port, 18 mm² flow area for medium-size cylinders).

Accessories: Silencers, flow control throttles, manifold bases for multi-valve centralized mounting.

Quick Selection Reference

Core Advantages of SHAKO PU520-02-S Solenoid Valve

Positioning: Taiwan-made internal-pilot 5/2-way solenoid valve. Benchmarked against SMC SY5120 and Airtac 4V310. High cost-performance, high flow capacity, robust for industrial conditions. Widely deployed in packaging, conveyors and special-purpose automation machines.

1. Excellent Flow Performance

Effective sectional area 18 mm², G1/4 port. Delivers high flow within compact footprint. Drives Φ32-Φ80 double-acting cylinders with fast response, avoids sluggish cylinder movement or insufficient thrust.

Body width only 26 mm, space-saving inside cabinets. Supports multi-valve stacking on MF520 manifold bases.

2. Robust Mechanical Construction

Anodized aluminum alloy valve body, abrasion and corrosion resistant. NBR spool seals resist oil contamination in factory compressed-air systems, long service life for continuous cyclic operation.

Coil rated for 100% continuous duty (ED100%), withstands permanent energization without burnout. Insulation class F, IP65 protection, good tolerance to workshop dust and humidity.

Voltage options: DC24V, AC220V, AC110V. Optional LED indicator lamps, E1 explosion-proof coils for hazardous-area applications.

3. Convenient Commissioning & Maintenance

Lockable manual override button: Press to force spool shift; rotate to release. Permits cylinder testing without electrical power, great for on-site commissioning and troubleshooting.

Standard DIN socket connection. Coil can be replaced individually without removing entire valve body; reduces spare-part costs.

Two pilot configurations available: standard internal-pilot PU520-02-S; low-pressure PU520A-02-S external-pilot variant, same valve housing for flexible specification change.

4. Comprehensive Product Portfolio

Full series covers 5/2-way single / double solenoid, plus 5/3-way valves (center exhaust / center pressure / center closed). G / Rc / NPT thread options for domestic and export equipment.

-S spring-return improves safety by returning actuators to safe state on power loss; -D latching double-solenoid for gate mechanisms requiring position retention.

5. Cost-Effective Supply

Performance comparable to SMC SY5120 series at lower price point; higher reliability than low-end generic domestic valves, suitable for mass machine OEM.

Ample stock availability across domestic distributors; easy procurement and field replacement, widely adopted for custom automation machinery.

6. Limitations & Selection Notes
7. Internal-pilot model requires minimum supply pressure ≥0.15 MPa. Use PU520A-02-S external-pilot for low-pressure air supply.
8. Not designed for ultra-high-frequency cycling (tens of cycles per second). Optimized for typical machine cycle rates.
9. Standard version not suitable for direct outdoor or heavy-corrosion exposure; add protective measures.

Selection Summary

✅ Prefer PU520-02-S: Packaging machines, conveyor lines, fixture jigs, general-purpose automation, stable air supply, seeking balance of performance and cost.

✅ Supply pressure below 0.15 MPa: Specify PU520A-02-S external pilot.

✅ Cylinder position must hold after power cut: Select PU520-02-D double solenoid.

SHAKO Main Solenoid Valve Models

SHAKO solenoid families: PU series (classic high-flow), BM series (new compact series), PU322 / BM320 (3/2-way). 5-port valves for double-acting cylinders; 3-port valves for single-acting cylinders / vacuum suction cups.

PU Series (Classic Line, PU520-02-S belongs to this family)

Body width 26 mm, high flow, compatible with MF520 manifolds. Suffix-A = external pilot for low-pressure operation.

5/2-Way Solenoid Valves

5/3-Way Solenoid Valves (Dual-coil, cylinder intermediate stop)

PU530-02-D-X: Center exhaust, A/B ports vented, cylinder free-floating

PU530-02-D-Y: Center pressure, A/B ports pressurized

PU530-02-D-Z: Center closed, A/B ports sealed for cylinder position lock

Port options 02(G1/4), 03(G3/8), 04(G1/2).

3/2-Way PU322 Series (Suction cups, single-acting cylinders)

PU322-02-S: G1/4, single solenoid, normally closed

PU322-02-N-S: Normally open, air passes when coil de-energized

BM Series (New compact replacement for PU series)

Identical functional performance, interchangeable mounting dimensions, MF520 manifold compatible.

5/2-Way

BM520-02-S: G1/4 single solenoid spring return (direct equivalent to PU520-02-S)

BM520-02-D: G1/4 double solenoid

BM520A-02-S/D: External-pilot variants

BM520-03-S/D, BM520-04-S/D: Larger port sizes

5/3-Way

BM530-02-D-X (center exhaust), BM530-02-D-Y (center pressure), BM530-02-D-Z (center closed)

3/2-Way BM320 Series

BM320-01-S (G1/8), BM320-02-S (G1/4), for suction cups and single-acting cylinders.

Complete Suffix Definition (Order Reference)

Order example: PU520-02-S-9-L：PU520, G1/4 port, single solenoid, DC24V, with LED indicator.

Matching Manifold Bases

MF520-02-02: PU/BM520 manifold base, G1/4, 2-station; 03=3-station. Multi-station configurations available for centralized air supply and exhaust.

Quick Selection Guide

1. Standard automation, cylinder auto-retract on power loss: PU520-02-S / BM520-02-S
2. Cylinder position retention required after power-off: Select -D double solenoid
3. Supply pressure below 0.15 MPa: Order external-pilot variant PU520A-02-S
4. Cylinder intermediate stop function: PU530 / BM530 5/3-way (choose center-exhaust / center-pressure / center-closed)
5. Suction cup or spring-return single-acting cylinder: PU322 / BM320 3/2-way

PU vs BM Series Comparison