5 inputs determine the right sensors & switche.

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
   Which variable does the machine need to confirm — cylinder position, air pressure, or vacuum grip?

   This is the root sort. Rod position → cylinder position sensor (magnetic auto-switch on the cylinder body). System or filter pressure → pressure sensor (single-point or differential). Pick-and-place grip → vacuum sensor / switch. Each watches one physical variable; there's no one device that covers all three.
2. 02
   What's the output type and voltage on the PLC input card?

   The most common cause of a dead sensor at commissioning is a mismatched signal type. PNP vs. NPN, switched vs. analog vs. IO-Link, and the supply voltage all have to match the input card. Pull the card spec sheet before quoting — and on safety circuits, confirm normally-open vs. normally-closed.
3. 03
   For a position sensor — what cylinder series is it mounting on, and what's the duty cycle?

   The sensor is selected to the cylinder series, not chosen independently — the mount (groove / T-slot, or band / strap) and the piston magnet match a specific family. Then set reed vs. solid-state by duty: solid-state for high-cycle and safety-critical motion, reed for lower-cycle, cost-sensitive work.
4. 04
   For a pressure sensor — single-point reading, or a differential across a filter?

   Single-point system pressure needs one tap; filter differential needs two taps (a pair, or one differential sensor). It changes the count and the part. Then size to the working-pressure range and the port thread at the install point, and pick gauge output for status-only vs. an electrical signal where it feeds control logic.
5. 05
   For a vacuum switch — what's the steady-state vacuum, and does the circuit also run positive blow-off?

   Set points sit relative to steady-state vacuum (grip-confirm and drop-detect), and they re-verify whenever the workpiece changes because cup volume and surface shift the thresholds. If the same line alternates vacuum grip with positive pressure, spec the compound variant — a vacuum-only switch faults on positive pressure.