Solar Charging Controller K1688, 20A A compact, userfriendly solar charge controller designed for 12 V and 24 V systems with automatic voltage detection. Housed in a durable ABS case and finished in orange, this controller combines clear LCD monitoring, adjustable charging parameters, USB device charging, and reliable protection features for small to medium offgrid solar setups. Key benefits Automatic 12 V and 24 V adaptation simplifies installation and prevents wiring errors. Adjustable charge and discharge thresholds protect battery state and allow system fine tuning for different battery types. Large LCD display provides immediate status information including charging current, discharge current, cumulative generation, discharge power, and temperature for easy system monitoring. Two 5 V USB outputs up to 2.5 A each let you charge mobile devices directly from the controller. Light control and delay control enable timed or dusktodawn operation for lighting loads. Three stage charging management and backflow protection improve charging efficiency while minimizing heat generation. Main functions and performance Model: K1688 Rated current: 20 A Material: ABS Color: Orange System voltage: 12 V and 24 V automatic adaptation Maximum photovoltaic input voltage: 50 V Maximum photovoltaic input power for 20 A version: 260 W at 12 V, 520 W at 24 V USB output: 2 x 5 V, up to 2.5 A (maximum) per port, supports iOS device charging Charging algorithm: 3 stage charging management with boost and float stages Boost charging voltage: 14.4 V Floating voltage: 13.7 V (default, adjustable) Discharge cutoff voltage: 10.7 V (default, adjustable) Discharge recovery voltage: 12.6 V (default, adjustable) Charging recovery voltage: 13 V Backflow protection to prevent battery discharge through the solar input at night Low heat generation for improved conversion efficiency Operating temperature: 35 to +60 C Standby current: not specified in product information Controls and indicators Large LCD display shows charging and discharging current, cumulative energy generation, discharge power records, and temperature. Adjustable charging and discharging parameters via onboard settings. Light control function for automatic load switching based on ambient light. Delay control to set delayed switchon or switchoff intervals. Poweroff memory retains settings after shutdown. Package contents 1 x Solar Charging Controller K1688 (20 A) 1 x English User Manual Practical applications Offgrid cabin or small cottage: Manage a 12 V or 24 V battery bank for LED lighting, small appliances, and device charging while monitoring system performance on the LCD. Recreational vehicle and boat systems: Charge and maintain service batteries, provide USB charging for phones and tablets, and control cabin lighting with light control and delay features. Remote lighting or signage: Power LED lighting with automatic dusktodawn control and adjustable timing to match site requirements. Compatibility and installation notes Designed for use with 12 V and 24 V battery systems. The controller automatically detects system voltage. Ensure photovoltaic array opencircuit voltage does not exceed 50 V. For the 20 A model, match the PV array to a maximum of 260 W at 12 V or 520 W at 24 V to stay within rated input power. Follow the included English user manual for wiring, programming voltage thresholds, and configuring light and delay settings. This controller provides clear monitoring, flexible configuration, and direct USB charging for compact solar installations where straightforward control and reliable performance are required.