The FC-300+PM-300 combines a stepper-motor-driven needle valve body with a digital controller that accepts analog and digital setpoint commands for closed-loop proportional flow regulation. Unlike solenoid-driven proportional valves, the stepper motor holds position at zero power — no dither, no coil heating drift, no minimum pilot pressure required. The PM-300 reads encoder feedback at 1.587×10⁻³ mm resolution and corrects position in real time, delivering ±0.1% F.S. repeatability across the full 0–400 L/min (air) range.

What control interfaces does the PM-300 support?

The PM-300 accepts 0–10 VDC, 4–20 mA, and RS485 Modbus RTU commands. The analog inputs provide drop-in compatibility with PLC analog output cards. RS485 Modbus enables digital setpoint control, multi-valve addressing on a single bus, and read-back of actual valve position when the encoder option is fitted. An LED on the controller indicates motor run, stop, and fault states at a glance.

How do I select the right body and seal material?

The FC-300 is offered in three body materials: aluminum for general-purpose air and inert gas, stainless steel 316L for corrosive fluids and clean-in-place environments, and PEEK for ultra-high-purity or aggressive chemical service. Seal options are Viton (standard, -20°C to +200°C) and FFKM (perfluoroelastomer, for strong oxidizers and extreme chemical resistance). The material choice is fully configurable at order time — not a fixed SKU.

How does the FC series scale across flow ranges?

Frequently Asked Questions

Does the valve fail closed on power loss?

Yes — in a different way than a spring-return solenoid valve. The stepper motor holds position when energized. On power loss, the motor loses holding torque and the valve remains at its last position. Configurations with fail-safe spring return are available on request. For critical applications requiring guaranteed closure on power loss, specify the fail-safe option at order time.

Can one PM-300 drive two FC valves independently?

No. Each PM-300 controller drives one FC valve body. For multi-channel flow control, use one PM-300 per FC valve, and address each via its own Modbus ID on a shared RS485 bus.