THEBEN SEL174top3 Astro Digital Time Switch, 2-Channel, Weekly/Astro Program, 230 V AC, DIN Rail, 2 Modules, 10-Year Power Reserve

Where conventional timers simply switch at fixed hours, the SEL174top3 Astro aligns your electrical loads with the natural rhythm of daylight. Its astronomical program calculates sunrise and sunset for your exact location, adjusting switching times daily without manual intervention—ideal for outdoor lighting, signage, or any application where daylight-dependent control saves energy and enhances security. Two independent channels, each with a potential-free changeover contact, provide flexible control for lighting, heating, ventilation, or other loads in residential, commercial, and industrial settings.

Highlights

• Astronomical function with offset adjustment: automatic switching based on sunrise/sunset times, with individual offset per channel
• 2 channels, each with potential-free changeover contact (NO/NC), rated up to 16 A resistive, 10 A inductive
• 10-year lithium battery power reserve: programs and time are retained during power outages
• Intuitive programming via high-resolution LCD, optional OBELISK top3 memory card, or Bluetooth dongle with app
• Zero-cross switching extends relay life and reduces inrush currents; external input, holiday program, and random function add flexibility
• Compact DIN rail mounting, only 2 modules (36 mm) wide; IP20 protection, operating temperature -30 °C to +55 °C

In daily use

The SEL174top3 Astro simplifies time-based control even for complex schedules. The menu-driven interface guides you through setup, while the optional OBELISK top3 memory card allows you to copy programs between devices or configure them on a PC. The Bluetooth dongle (sold separately) enables wireless programming via smartphone app, making adjustments quick and convenient. The external input can be used for manual override or integration with other systems, and the PIN code protects against unauthorized changes. The holiday program lets you define exceptions for vacations, and the random function simulates presence for added security. With a time accuracy of ±0.25 s/day at 25 °C, you can rely on precise switching. The 10-year power reserve ensures that even after extended power failures, your settings remain intact and the device resumes operation seamlessly.

Full specifications

• Number of channels: 2
• Program type: Astronomical, Weekly
• Operating voltage: 230 V AC, 50 – 60 Hz
• Switching output: 2x potential-free changeover contact (NO/NC)
• Max. switching capacity resistive: 16 A (250 V AC, cos φ = 1)
• Max. switching capacity inductive: 10 A (250 V AC, cos φ = 0.6)
• Incandescent/halogen lamp load: 2600 W
• LED lamp load (typ. capacitive): 600 W
• Shortest switching time: 1 minute
• Power reserve: 10 years (lithium battery)
• Mounting type: DIN rail, 2 modules (36 mm)
• Display: High-resolution LCD
• Programming options: Device, OBELISK top3 memory card, Bluetooth (via dongle/app)
• Operating temperature: -30 °C to +55 °C
• Protection class: IP20
• Time accuracy: ±0.25 s/day (at 25 °C)
• Special functions: Astro function, offset, holiday program, random function, external input, PIN code, zero-cross switching

Final note

For precise, energy-efficient control of lighting and other loads based on the sun's position, the SEL174top3 Astro offers a robust, feature-rich solution that fits seamlessly into any distribution board.