Welcome to Chilli Jam Vans, your van conversion specialists based in Cornwall. The D250SE is a fully automatic, 5 step charger that supplies up to 20A of power to any 12V lead-acid or lithium service battery from 40-300Ah. It has selectable charge algorithms for flooded, AGM and lithium batteries and can use power from both the alternator and a solar panel or a wind turbine. The D250SE can maintain a stable output up to 20A to vehicles fitted with smart, ECU controlled alternators and also has a temperature sensor for optimised charging, regardless of weather conditions. The D250SE is designed for use with solar panels rated at up to 300W but won’t be damaged if a larger panel is connected – as long as the voltage from the panel is no more than 23V. (Open Circuit Voltage cannot exceed a MAXIMUM of 23V) Connecting a larger panel is actually a good way of compensating for poor perfomance on cloudy days! The D250SE also features a battery maintenance function which sends 3-second pulses to the starter battery every 15 seconds. The current will vary according to the amount of power coming from the solar panel and the voltage at the starter battery. Ideal for use in campervans, especially if they have smart alternators, the D250SE can be used on its own or with a CTEK Smartpass. The Smartpass 120S is also lithium compatible. If you have any questions about this product, or any of our other products, please get in touch with the Chilli Jam Vans team.