A pneumatic solenoid valve is the core component that controls the direction of cylinder motion on a pneumatic line: the PLC sends an ON/OFF signal to the valve coil, the spool inside the valve switches the air path, and the cylinder extends or retracts. Without a solenoid valve, a PLC cannot control a pneumatic mechanism. Options include 5/2, 5/3 and 3/2-way valves, AC 110/220 V or DC 24 V coils, and 1/8 or 1/4 ports (FESTO MFH uses G threads, e.g. G1/8). Typical uses: SMT fixture clamping cylinders, robots, tray lifts and conveyor gates.
This series covers 3 models of 5/2-way directional valves across FESTO and SMC: FESTO MFH-5-1/8, FESTO MFH-5-1/4 B and SMC SY3220-5LOZ-M5 (the last two are not listed on this page, available on request).
A JIAHON affiliated company supplies customers throughout Taiwan.
Models in this series (3 × 5/2-way valves)
| Model | Brand | Valve type | Port | Typical application |
|---|---|---|---|---|
| MFH-5-1/8 | FESTO | 5/2-way | G1/8 | Direction control of medium cylinders (bore 32–50 mm) |
| MFH-5-1/4 B (not listed on this page, available on request) | FESTO | 5/2-way | G1/4 | Direction control of large cylinders (bore 50–80 mm); the B suffix may indicate a special variant (check the official FESTO catalog) |
| SY3220-5LOZ-M5 (not listed on this page, available on request) | SMC | 5/2-way double solenoid | M5 (miniature) | SMT fixtures, IC programming sockets, small cylinders (bore 16–25 mm) |
Note: FESTO MFH-5-1/8 and MFH-5-1/4-B are 5/2 single-solenoid valves (spring return); FESTO’s double-solenoid versions are the JMFH series (available on request). The “B” suffix on MFH-5-1/4 B may indicate a special variant or configuration — confirm with the official FESTO catalog. SMC SY3220-5LOZ-M5 model code: SY3000 series (3) + 2-position double solenoid (2) + body-ported (20) + DC 24 V (5) + L-type plug connector without connector (LO) + with indicator light / surge suppressor (Z) + M5 port.
Specifications (general range)
| Item | Range |
|---|---|
| Valve type | 3/2-way (single-acting cylinder) / 5/2-way (double-acting cylinder, most common) / 5/3-way (mid-position stop) |
| Actuation | Single solenoid (spring return; MFH-5-1/8 on this page) / double solenoid (holds position when power is off) |
| Coil voltage | AC 110 V / AC 220 V / DC 24 V (common) / DC 12 V; the MFH-5-1/8 valve body on this page does not include a coil — order the coil separately by voltage |
| Coil power | Typically 1–4 W (DC 24 V) / 2–6 VA (AC) |
| Operating pressure | 0.15–0.8 MPa (standard); some high-flow types 0.05–0.8 MPa |
| Medium | Dry, clean compressed air (5 μm filter + lubricator recommended; lubricator can be omitted for lube-free types) |
| Operating temperature | −5 °C to +50 °C (standard) |
| Ports | M3 / M5 (miniature) / 1/8 / 1/4 / 3/8 / 1/2 PT (medium and large) |
| Response time | 5–15 ms (DC) / 30–50 ms (AC) (typical) |
| Mechanical life | Typically ≥ 500,000 cycles |
| Mounting | Individual / manifold (multiple valves on one base) |
Note: these are general ranges for pneumatic solenoid valves; actual valve type, ports, voltage and response time depend on the brand catalog and model version.
Applications
Solenoid valves are the pneumatic “nerves” of SMT, semiconductor, packaging and food lines, used from fixture clamping to conveyors. Four typical applications:
- SMT fixture clamping and pressing: SMT placement fixtures, IC programming sockets and test socket pressing mechanisms use 16–25 mm bore cylinders with small M5-port 5/2 double-solenoid valves (such as SMC SY3220-5LOZ-M5). The double-solenoid design holds the clamp when power is lost, so parts are not dropped.
- Robot pick-and-place pneumatic joints: pneumatic X/Y/Z joints and gripper open/close on robots use 25–50 mm bore cylinders with 1/8 or 1/4-port 5/2 valves (such as FESTO MFH-5-1/8, G thread, single solenoid with spring return). High cycle rates make response speed important (DC 24 V is better).
- Tray lifts / conveyor gates: long-stroke motions such as tray lifts and conveyor diverter gates use 50–80 mm bore cylinders with 1/4 or 3/8-port 5/2 valves (such as FESTO MFH-5-1/4 B, G thread). Add speed controllers to control motion speed and avoid impact.
- Semiconductor vacuum / chemical valves: CVD/PVD vacuum valves and chemical valves need special specifications such as direct-acting, all-stainless-steel or PTFE seals. These are not general pneumatic solenoid valves; use the brands’ vacuum/chemical series (such as SMC VDW, CKD AB31).
Selection guide
| Application | Recommended valve type | Port | Coil | Suggested models |
|---|---|---|---|---|
| SMT fixture (bore 16–25 mm) | 5/2 double solenoid | M5 / 1/8 PT | DC 24 V | SMC SY3220-5LOZ-M5 |
| Robot pick-and-place (bore 25–50 mm) | 5/2 single or double | 1/8 PT | DC 24 V | FESTO MFH-5-1/8, SMC SY5120 |
| Tray lift / gate (bore 50–80 mm) | 5/2 single solenoid | 1/4 PT | AC 220 V or DC 24 V | FESTO MFH-5-1/4 B, SMC SY7120 |
| Large pneumatic actuators | 5/2 high-flow | 3/8–1/2 PT | AC 220 V | FESTO JMFH series, SMC VFS |
| Stop at mid-position on power loss (safety stop) | 5/3 closed center | As required | DC 24 V double | SMC SY5240, FESTO MFH-5/3 |
Note: this table is a general reference; ports, voltage and mounting must match your existing cylinders and PLC. FESTO and SMC mounting dimensions differ, so cross-brand replacement usually means changing the sub-base and piping as well.
5/2 vs 5/3 vs 3/2-way: how to choose
| Valve type | Construction | Cylinder | Common use |
|---|---|---|---|
| 5/2-way | 5 ports + 2 positions | Double-acting | SMT fixtures, robots, tray lifts — most common in factories |
| 5/3-way | 5 ports + 3 positions | Double-acting + mid-position stop | Stop at mid-position on power loss (closed center), safety mechanisms |
| 3/2-way | 3 ports + 2 positions | Single-acting | Air blow nozzles, one-way motion, gripper pressing |
Rule of thumb: (1) double-acting cylinder controlled in both directions → 5/2-way; (2) double-acting cylinder that must stop in the middle or hold its position on power loss → 5/3-way; (3) single-acting cylinder or one-way motion → 3/2-way. In the FESTO MFH-5 series, the “5” indicates a 5/2-way valve.
Single vs double solenoid: what happens on power loss
| Type | Construction | State after power off | Use |
|---|---|---|---|
| Single solenoid | Coil on one side + spring on the other | Spring returns to home position | Gates that close automatically, grippers that release, safety return mechanisms |
| Double solenoid | Coils on both sides | Holds current position (latching) | Fixture clamps that must not release on power loss; holding position long-term without power |
Decision logic: “Where should the cylinder be after power is lost?” Back to home → single solenoid; stay where it is → double solenoid. Because a double-solenoid valve does not need continuous power to hold position, it actually saves energy when holding a state for long periods, though the valve costs more.
AC vs DC coils: response, life, protection
| Item | AC coil (110 V / 220 V) | DC coil (24 V) |
|---|---|---|
| Response | 30–50 ms | 5–15 ms |
| Switching arc | Yes (shorter life) | None |
| Back EMF | Needs snubber protection | Needs flyback diode protection |
| Direct PLC drive | Needs relay output or interposing relay | Can be driven directly by transistor output |
| Use | Integration with AC power systems via relays | New machines, direct PLC connection, fast response |
In practice: most new SMT, semiconductor and automation machines use DC 24 V — fast response and simple direct drive from PNP transistor DO modules. Older plants with AC power systems or large pneumatic actuators use AC 220 V. A flyback diode is essential on DC solenoid valves (it protects the PLC module) and must not be omitted.
Selection steps and cross-brand replacement notes
Selection steps: valve type (5/2 / 5/3 / 3/2, by cylinder motion) → single or double solenoid (required power-off state) → coil voltage (AC 110/220 V, DC 24 V) → port size (M5 / 1/8 / 1/4 / 3/8 PT) → brand (this page lists FESTO MFH-5-1/8; other brands available on request).
Each brand names its models differently: FESTO MFH-5-1/8 = MFH series + 5/2-way + 1/8 port; SMC uses completely different naming logic (see the model code note above). For cross-brand replacement, match item by item — not just “both are 5/2-way”.
Manifolds: direct cross-brand replacement is almost never possible — manifolds are brand-specific.
Trademarks: FESTO, SMC, CKD, KOGANEI, AIRTAC and the model names on this page are trademarks or model names of their owners, used here only to identify the products. JIAHON is not the authorized distributor of these brands in Taiwan.
Request a quote
Need a quote or want to confirm specifications? Send us the model and quantity. Request a quote →