If you cannot afford to lose the program currently running on the PLC, standard factory resets will not help. You cannot read a password-protected program off a card directly, but you can overwrite the password block if you have a backup of the original project file without the password. Step-by-Step Procedure Power down the PLC and remove the . Insert the SMC into your PC card reader.
Doing so will permanently destroy the hidden system files required by Siemens hardware, rendering the expensive card completely useless. Step-by-Step Procedure to Clear the Password Power down the S7-1500 PLC rack. Open the front flap of the CPU and eject the SMC .
Best for: Quickly clearing a PLC that has a display screen attached, provided display privileges aren't locked.
Since the S7-1500 stores its configuration and password on the SIMATIC Memory Card , you can reset the password by clearing the card: Remove the SIMATIC Memory Card siemens s7-1500 password reset
Prevent unauthorized personnel from performing a hardware factory reset by placing a PIN protection code specifically on the physical CPU display menu ( Settings > Display > Protection ).
Open Windows File Explorer and navigate to the card directory.
Locate the card directory. You will see a folder named SIMATIC.S7S and a file named S7_JOB.S7S . both the SIMATIC.S7S folder and the S7_JOB.S7S file. If you cannot afford to lose the program
Navigate to the Device Configuration in TIA Portal.
On CPUs with a built-in display, use the front buttons to navigate to Settings > Reset > Factory Reset .
Do NOT delete hidden files like __LOG__ or crdinfo.bin , as these make the card recognizable to the PLC. Insert the SMC into your PC card reader
Double-click the discovered CPU to open the “Online & Diagnostics” view. Navigate to Functions → Reset to factory settings .
Before performing a reset, it is vital to understand what you are dealing with. The S7-1500 implements multiple layers of security, and not all of them are affected equally by a "factory reset":
You will find many websites and vendors offering "Siemens S7-1500 password decryption," "password recovery software," or "unlocking services." These should be approached with extreme caution due to the severe risks involved.
This write-up explores the technical realities of resetting passwords on the S7-1500, the implications of the "Know-How Protection" feature, and the necessary procedures for factory resetting the device when credentials are lost.
If the hardware allows, you can perform a reset directly on the PLC's screen.