Siemens SIMATIC S7 System Manual page 146

PLC device configuration
6.1 Configuring the operation of the PLC system
Accessing a password-protected CPU
Note
When you enter the password for a password-protected CPU, the authorization level for that
password remains effective for up to one minute after the programming device has been
disconnected from the S7-200 SMART CPU. Always exit STEP 7-Micro/WIN SMART before
disconnecting the cable to prevent another user from unauthorized access.
Entering the password over a network does not compromise the password protection for the
S7-200 SMART CPU. If one authorized user is accessing restricted functions across a
network, that does not authorize other users to access those functions. Only one user is
allowed unrestricted access to the S7-200 SMART CPU at a time.
Disabling a password
You can disable the password by changing the privilege level 4, 3, or 2 to "Full privileges"
(Level 1), since Level 1 allows all unrestricted CPU access.
Note
If the privilege level is at "Disallow Upload" (Level 4), you cannot download a new system
block with a new password level if a valid user program exists. You must delete the user
program first, and then you can download an updated system block.
What to do if you forget the password
If you forget your password, you must reset your PLC to factory defaults. (Refer to clear PLC
memory (Page 164) for more information.)
146
System Manual, V2.3, 07/2017, A5E03822230-AF
S7-200 SMART