Siemens SIMATIC S7-200 System Manual page 63

Configuring a Password for the S7-200
The System Block dialog box (Figure 4-32) allows you to configure a password for the S7-200.
The default condition for the S7-200 is set at Full (Level 1), no restriction.
1. Select the View > Component >
System Block menu command to
display the System Block dialog
box and select Password.
2. Select the appropriate level of
access for the S7-200.
3. Enter and verify the password for
Partial (Level 2) or Minimum
(Level 3).
4. Click OK.
5. Download the modified system
block to the S7-200.
Recovering from a Lost Password
If you forget the password, you must clear the memory of the S7-200 and reload your program.
Clearing the memory puts the S7-200 in STOP mode and resets the S7-200 to the factory-set
defaults, except for the network address, baud rate, and the time-of-day clock. To clear your
program in the S7-200:
1. Select the PLC > Clear menu command to display the Clear dialog box.
2. Select all three blocks and confirm your action by clicking OK.
3. If a password had been configured, STEP 7--Micro/WIN displays a password-authorization
dialog box. To clear the password, enter CLEARPLC in the password-authorization dialog
box to continue the Clear All operation. (The CLEARPLC password is not case sensitive.)
The Clear All operation does not remove the program from a memory cartridge. Since the memory
cartridge stores the password along with the program, you must also reprogram the memory
cartridge to remove the lost password.
Warning
Clearing the S7-200 memory causes the outputs to turn off (or in the case of an analog output,
to be frozen at a specific value).
If the S7-200 is connected to equipment when you clear the memory, changes in the state of the
outputs can be transmitted to the equipment. If you had configured the "safe state" for the
outputs to be different from the factory settings, changes in the outputs could cause
unpredictable operation of your equipment, which in turn could cause death or serious injury to
personnel, and/or damage to equipment.
Always follow appropriate safety precautions and ensure that your process is in a safe state
before clearing the S7-200 memory.
PLC Concepts
Figure 4-32 Creating a Password
Chapter 4
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