Successful testing SQ8W-100 automatic transfer switch (ATS), Marstek Jupiter (E / C) energy storage units, Marstek Venus inverters / AC-coupled batteries, and the Marstek CT002 smart meter. Each section explains what the device does, gives short technical highlights and suggests typical DIY applications. Keywords: DIY solar, home energy storage, solar battery, MPPT controller, solar inverter, automatic transfer switch, zero-feed-in.