Siemens Key-operated switch, 2 positions, lock number 421 Part number 3SU1000-4DF11-0AA0

Product Overview

The Siemens 3SU1000-4DF11-0AA0 is a key-operated switch from the RONIS series, designed for front-panel operator control. It features a 22 mm mounting diameter, plastic black front ring, silver metal key actuator (Lock No. 421), and offers two switch positions (O and I) with key removal in both positions.

Key Features

• Key-operated switch (RONIS lock No. 421) with 2 keys supplied
• 22 mm round actuator, front ring diameter ~29.5 mm
• Actuating angle: 90° (positions at 10:30 h / 13:30 h) with latching function
• Key removable in both O and I positions (O+I) for secure operation
• Protection class of actuator front: IP66 / IP67 / IP69K; terminations rated IP20
• Designed for front-panel mounting with mounting depth ~25.4 mm

Technical Specifications

• Product Series: SIRIUS ACT – Key-Operated Switches
• Article Number: 3SU1000-4DF11-0AA0
• Actuating Element: Key, metal, silver finish
• Mounting Diameter: 22.3 mm (+0.4 mm tolerance)
• Installation Depth: 25.4 mm
• Mounting Dimensions (H×W): 49.4 mm × 29.5 mm
• Mechanical Service Life: ~1 000 000 switching cycles
• Shock Resistance: 15 g / 11 ms (IEC 60068-2-27)
• Vibration Resistance: 10-500 Hz at 5 g (IEC 60068-2-6)
• Ambient Temperature (Operation): –25 °C to +70 °C
• Storage Temperature: –40 °C to +80 °C

Compliance & Certifications

• Protection front: IP66 / IP67 / IP69K; terminals: IP20
• NEMA ratings: 1, 2, 3, 3R, 4, 4X, 12, 13
• Complies with Siemens industrial-automation standards for operator control elements

Applications

The 3SU1000-4DF11-0AA0 key-operated switch is ideal for machine-control panels, safety interlock systems, and industrial automation interfaces where secure key removal in either operating position is needed. Its high protection rating and robust design make it suitable for harsh-environment use, such as in manufacturing plants, outdoor cabinets or maintenance-critical installations.