The Siemens 5SY1702-4 is a SENTRON device protection switch, single-pole with an auxiliary switch (1P+AS), rated 2 A at AC and 60 V DC (max 72 V DC). It carries the F2 tripping characteristic, designed for semiconductor and sensitive load protection where fast response to overcurrents is needed. The switch meets IEC/DIN EN 60934 and UL1077 standards, so it is accepted in both IEC and North American panels.
The 2 A AC rating is the nominal current at 50/60 Hz. For panel builders working in elevated ambient temperatures, the rated current derates: 1.93 A at 35 °C, 1.83 A at 40 °C, 1.78 A at 45 °C, 1.73 A at 50 °C, 1.67 A at 55 °C, and 1.62 A at 60 °C. Use the 40 °C value (1.83 A) for most enclosed panel designs unless the ventilation is generous. It mounts horizontally or vertically.
Compliance documentation includes the IEC/DIN EN 60934 and UL1077 certifications on the nameplate. The product designation per EN 61346-2 and IEC 81346-2 is letter F (protective device).