Why is my CTEK D250S Dual not charging my batteries?
Your CTEK D250S Dual won't charge your batteries if your batteries are below 13.2V.
To ensure your CTEK D250S Dual charges your batteries you must connect a battery with a voltage higher than 13.2V. This is because the CTEK D250S Dual is designed with a cut-out voltage of 13.2V, in order to prevent drain from your start battery, ensuring you have enough power to start your vehicles.
Another issue which may cause charging issues, is the connection of your solar panel. The CTEK D250S Dual will only charge from solar panels when the vehicle is turned off. It is also unable to charge from solar panels with built in solar regulators, so you must ensure that the solar panel you use with your CTEK D250S Dual does not have a built in solar regulator.