The Siemens 5SY1704-2 is a SENTRON device protection switch — a 1-pole unit with an integrated auxiliary normally-open contact, rated 4 A with F1 tripping characteristic. It interrupts fault currents up to 3 kA AC per IEC 60934 and carries UL1077 recognition, so it qualifies for both IEC and North American panel builds. The auxiliary switch signals the breaker's state without needing a separate contact block, saving one modular width on the DIN rail.
The F1 characteristic trips magnetically on short-circuit. The 4 A rating governs the continuous load; at 230 V AC single-phase the switch is rated for 250 V maximum, and at DC it handles 60 V nominal (72 V max). Mounting is standard DIN-rail snap-on, one modular unit wide (18 mm). The part can be mounted horizontally or vertically, and the supply cord position is unrestricted — no fixed line/load orientation. IP20 finger-safe protection is sufficient for enclosed panels; the sealable option (yes) allows locking the toggle to prevent unauthorized reset.
Deployment context
This device protection switch is designed for control-circuit protection in industrial panels — think PLC power supplies, contactor coils, solenoid valves, or small transformer primaries where the F1 curve matches the inrush profile. The halogen-free and silicon-free construction is relevant for clean-room or automotive paint-line environments where outgassing contaminants can't be tolerated. Vibration resistance per IEC 60068-2-6 means it holds up on machine-mounted subpanels near motors or presses.