Sensors and limit switches

Sensors convert physical conditions into control-system signals. They detect presence and position, monitor pressure or level, and provide feedback on process operations.

The subcategories distinguish inductive, capacitive, photoelectric and ultrasonic detection, pressure sensing and mechanical position. Eaton E57 detects metal targets, E53 uses a capacitive principle and E65/E71 a light beam. Siemens SITRANS Probe LU240 measures level through ultrasonic echoes. Eaton MCS pressure switches respond at set thresholds, while LS uses mechanical actuation. Target material, mounting, environment and response requirements determine selection and matching to controller inputs.