S7-400H
System Manual, 03/2012, A5E00267695-11
77
Special functions of a CPU 41x-H
6
6.1
Security levels
You can define a security level for your project in order to prevent unauthorized access to
the CPU programs. The objective of these security level settings is to grant a user access to
specific programming device functions which are not protected by password, and to allow
that user to execute those functions on the CPU. When logged on with a password, the user
may execute all PG functions.
Setting security levels
You can set the CPU security levels 1 to 3 under "STEP 7/Configure Hardware".
If you do not know the password, you can clear the set security level by means of a manual
memory reset using the mode selector. No Flash card must be inserted in the CPU when
you perform such an operation.
The following table lists the security levels of an S7–400 CPU.
Table 6- 1
Security levels of a CPU
CPU function
Security level 1
Security level 2
Security level 3
Display of list of blocks
Access granted
Access granted
Access granted
Monitor variables
Access granted
Access granted
Access granted
Module status STACKS
Access granted
Access granted
Access granted
Operator control and monitoring
functions
Access granted
Access granted
Access granted
S7 communication
Access granted
Access granted
Access granted
Reading the time
Access granted
Access granted
Access granted
Setting the time
Access granted
Access granted
Access granted
Block status
Access granted
Access granted
Password required
Load in PG
Access granted
Access granted
Password required
Load in CPU
Access granted
Password required
Password required
Delete blocks
Access granted
Password required
Password required
Compress memory
Access granted
Password required
Password required
Download user program to
memory card
Access granted
Password required
Password required
Controlling selection
Access granted
Password required
Password required
Modify variable
Access granted
Password required
Password required
Breakpoint
Access granted
Password required
Password required
Clear breakpoint
Access granted
Password required
Password required
Memory reset
Access granted
Password required
Password required
