9 inputs determine the right actuator.

A distributor-facing pre-quote checklist. If the customer answers most of these at the first call, the second call is the quote.

1. 01
   How many positions does the cycle actually need to hit?

   Two positions = rotary-pneumatic. Three or more positions = electric, no exceptions. Pneumatic actuators only know "end of stroke A" and "end of stroke B" — anything mid-travel needs a closed-loop electric or a stack of mechanical stops that won't hold tolerance long.
2. 02
   What's the angular travel and the torque the load actually demands?

   Standard pneumatic rotaries cover 90°, 180°, 270°; non-standard angles get expensive fast. Torque scales with bore and pressure for vane designs and with rack length for rack-and-pinion. Get the load inertia, not just the static torque — high-cycle indexing under-spec'd on torque will stall.
3. 03
   For electric — is this a drop-in retrofit or a new machine build?

   Retrofit conversations lead with the SMC LEY drop-in story: same mounting bolt pattern as the existing cylinder, same stroke, no machine rework. New builds get the full LEY + LEC controller + fieldbus conversation. Don't quote a clean-sheet servo when the customer just wants the cylinder gone.
4. 04
   What's the duty cycle — shift hours and cycles per minute?

   Electric actuator payback math hinges on duty. 24/7 multi-shift duty above 30 cycles/min pays back the electric capex in 18-36 months on air-cost savings alone. Single-shift light-duty work doesn't — pneumatic rotary stays right.
5. 05
   What positioning accuracy does the application need?

   Pneumatic rotary holds end-of-rotation to mechanical stops — typically ±1-2° repeatability. Anything tighter than ±0.5° angular or ±0.5 mm linear demands electric closed-loop. Spec'ing pneumatic for precision work is the most common over-promise in this category.
6. 06
   Is there an air-quality or air-cost conversation already happening at this plant?

   If the customer is doing an energy audit, has had a recent compressor upgrade conversation, or is paying $500-2,000/year per drain on timer-vented condensate, they're already primed for the electric-migration story. Lead with the SMC LEY retrofit; the math sells itself.
7. 07
   How will the actuator be controlled — PLC discrete, IO-Link, or fieldbus?

   Pneumatic rotary needs a 5-port valve and two PLC outputs — that's the whole control stack. Electric needs a controller, power supply, and a PLC fieldbus integration plan (LEC controller runs EtherNet/IP, EtherCAT, Profinet variants). Scope the controls integration before quoting.
8. 08
   Does the cycle need profiled motion — soft-start / soft-stop, mid-stroke pause?

   Any time the answer is yes, the spec is electric. Pneumatic can't profile without proportional valves and external controls that cost more than just switching to electric outright. Profiled motion = electric.
9. 09
   Is the end-of-rotation impact controlled, or will the actuator slam to stop?

   Pneumatic rotary at end-of-rotation slams into the mechanical stop at full cycle speed unless cushioned. High-cycle indexing duty needs internal cushions or external shock absorbers (see Motion Control). Skipping that destroys the actuator and the tooling alongside it within months.