marlin/config/examples/Creality/Ender-5/README.md

Creality Ender-5 Leadscrew Changes

In mid-to-late 2019, Creality upgraded the base Ender-5 leadscrew to the same one used on the Ender-5 Pro which prevents the bed from dropping once power is cut.

If your machine shipped with the upgraded leadscrew (or if your prints are ½ as tall as they should be), change your Z steps from 400 to 800 in Configuration.h:

Before: DEFAULT_AXIS_STEPS_PER_UNIT { 80, 80, 400, 93 }

After: DEFAULT_AXIS_STEPS_PER_UNIT { 80, 80, 800, 93 }

Or by sending M92 Z800 followed by M500 after updating your firmware.