Use a PC with a SIMATIC card reader to empty the card or load a simple project without password protection. Power Down: Turn off the power supply to the S7-1500 CPU.

Inserting an empty or specially prepared "Reset" Memory Card.

This will delete the IP address and protection passwords for configuration data. 2. Reset via Empty SIMATIC Memory Card (SMC)

If a memory card was configured as a (not just storage), inserting it overrides internal password protection. However, the card itself must have been pre-configured with the correct project.