SMC SY3120-5LZD-M5 Compact 5-Port Solenoid Valve

The smallest SY body for fast, light cylinders

SY3120-5LZD-M5 is the SY3000 size of SMC 5-port, 2-position single solenoid valve. It is the compact end of the range, with M5 x 0.8 ports and a 51 to 57 g weight depending on the connector, and is selected for small cylinders, grippers and rotary actuators on assembly and electronics machines where the stroke is short and cycling is fast.

The code is read as: SY3 (SY3000 size), 1 (2-position single), 20 (main valve style), 5 (24 VDC), L (L plug connector, 300 mm lead wires), Z (with light and surge voltage suppressor), D (push-turn locking slotted manual override) and M5 (M5 x 0.8 thread on the A and B ports). No bracket or thread-type suffix is shown.

Technical specifications

What the small flow figure means in practice

With a conductance of 0.61 dm3/(s.bar), the SY3120 suits small cylinders (as a rough guide, bores of the order of 6 to 16 mm, which is our estimate rather than a catalogue statement), where a quick, light valve matters more than flow. In the current SY3000/5000/7000 catalogue the rubber-seal 2-position valves are rated for a 5 Hz maximum, and only the metal-seal SY3000 versions are rated higher (20 Hz). The main reasons to choose the 3000 size are therefore its compact body, low weight and short response time, not a higher cycle rate. Do not expect the same speed on larger cylinders; the next size up is the SY5120-5LZD-01.

The compact solenoid draws 0.35 W (0.4 W with the indicator), so a PLC output card can usually drive it directly, although the output rating must be checked.

Installation and options

Piping is by M5 threaded fittings; one-touch fitting versions for 4 and 6 mm tube (C4, C6) are separate codes. A single unit ordered with this code is a body-ported valve, so it is mounted by its own mounting holes or a bracket, not on a sub-plate, and the manifold bolts and gasket are not included. Fit sound-damping silencers on the exhaust ports if the valve cycles quickly, and use filtered, dry air; the catalogue says lubrication is not required.

The compact body keeps the valve weight low, which helps on moving heads where the valve is mounted on the axis.

Documents and quotation

The SMC SY3000/5000/7000 catalogue PDF linked at the end of this page has the full order code table, specifications, flow data and dimensions. Please confirm voltage, connector, manual override and port thread before ordering. For more valves see Solenoid Valves. Seven Star LLC is an independent supplier and will quote this exact code on request.

How the SY3120-5LZD-M5 Works

The SY3120-5LZD-M5 is an internally piloted spool valve. When the 24 VDC coil is energised, the small pilot valve sends supply air from port 1 (P) to the main spool piston. The spool shifts so that port 1 feeds port 4 (A) and port 2 (B) exhausts through port 3. When power is removed, the pilot exhausts and the return spring resets the spool, so port 1 feeds port 2 and port 4 exhausts through port 5. A single-solenoid valve therefore always returns the actuator to the same position if power is lost. Because the pilot uses line air, at least 0.15 MPa must be available at port 1.

The Z option combines an LED indicator with a surge voltage suppressor (a diode in SMC’s specification). This makes fault-finding easier and protects the controller output from the coil’s switch-off voltage spike.

Series data from SMC’s SY3000/5000/7000 valve specifications

SY3120-5LZD-M5 Ordering Code at a Glance

• SY3 – SY3000 body size
• 1 – 2-position single solenoid, spring return
• 20 – body-ported single unit
• 5 – 24 VDC (6 would be 12 VDC)
• L – L plug connector with lead wire
• Z – indicator light and surge voltage suppressor
• D – push-turn locking slotted manual override
• M5 – M5 × 0.8 ports for A and B

Related codes differ by just one letter. For example, a grommet version, a 12 VDC coil or a one-touch fitting port each have their own letter, so a replacement should always be ordered from the full code on the existing valve label.

Installation & Maintenance

• Flush the piping before connecting it, and make sure no sealant or chips enter the small M5 ports.
• Tighten M5 fittings by hand and then a small additional turn with a tool. Over-tightening can damage the threads.
• Fit silencers on the exhaust ports, and use speed controllers on the cylinder to set its speed.
• After using the D type manual override, return it to the unlocked position before restarting automatic operation.
• Use filtered, dry air. If lubrication is introduced, keep supplying it continuously.

Typical Applications in Oman & the GCC

Typical uses across Oman and the GCC include small cylinders and grippers on packaging, labelling and assembly equipment, test fixtures, and laboratory or food-processing machines, where a compact valve can be mounted close to the actuator.

Why Source from Seven Star LLC

Seven Star LLC supplies SMC SY series valves, fittings and accessories across Oman and the GCC. Request a quote with the part number from your valve label, and our team can help confirm the correct ordering code.