Plug in a 40W–100W device (e.g., a lamp or phone charger). Do not test with a high-draw device like a heater. The manual recommends always starting with a low-wattage test.
Do not exceed 15A on the input side. If your source is 12V, your maximum theoretical power is 180W (12V x 15A), regardless of the 900W rating. bst900w manual
Ensure your input voltage is at least 2V lower than your target output. Plug in a 40W–100W device (e
The dedicates a full page to the LCD symbols. Here is the cheat sheet: Plug in a 40W–100W device (e.g.