U.4.8
SEL-421 Relay User’s Guide Date Code 20090715
Basic Relay Operations
Changing the Default Passwords
Communications Ports Access Levels
Entrance to the higher security levels is sequential. You must first enter a
correct password to move from Access Level 0 to Access Level 1.
This device is shipped with default
passwords. Default passwords should
be changed to private passwords at
installation. Failure to change each
default password to a private
password may allow unauthorized
access. SEL shall not be responsible
for any damage resulting from
unauthorized access.
!
WARNING
To enter Access Levels B, P, A, O, and 2, you must enter a correct password
from Access Level 1. For example, to go to the O (Output) Access Level from
Access Level 1, type OAC <Enter>. At the
Password: ? prompt, type your
Access Level O password.
To enter Access Level C, you must enter a correct password from Access
Level 2.
Use the relay QUIT command from any access level to return the relay to
Access Level 0. To reestablish control at a previous access level from Access
Level 1, you must use the access level commands and passwords to log in to
that previous access level.
When a connection with the SEL-421 times out, the relay reduces the access
level to Access Level 0 for that communications port connection.
The MAXACC port setting can be used to limit the maximum access level
permitted on a port. This can be useful to restrict what remote users can do.
Front-Panel Access Levels
The lowest access level for the front panel is Access Level 1. To enter Access
Levels B, P, A, O, and 2, you must enter a correct password from Access
Level 1.
The front-panel LCD displays a password prompt when you attempt to control
the relay at any access level higher than Access Level 1. (For more
information on entering passwords from the front panel, see Password on
page U.5.14.)
The front-panel
MAIN MENU item RESET ACCESS LEVEL returns the relay to
Access Level 1. In addition, when the front-panel inactivity timer times out
(indicated by the
ROTATING DISPLAY on the front-panel LCD), the relay
returns the front-panel access level to Access Level 1.
ACCESS Command
NOTE: You can shorten relay
commands to the first three letters of
the full command. See Section 9:
ASCII Command Reference in the
Reference Manual for more
information.
Enter the ACCESS (ACC) command to change to Access Level 1. Passwords
are case sensitive; you must enter a password exactly as set.
If you enter the password correctly, the SEL-421 moves to Access Level 1 and
the Access Level 1 => prompt appears. If you are at a higher access level (B,
P, A, O, and 2), you can reduce the access level to Access Level 1 by entering
the ACC command. The relay performs no password validation to reduce the
present access level.
Higher Access Level Commands
Enter the commands in Table 4 . 4 to enter access levels above Access Level 1.
For example, enter the 2ACCESS (2AC) command to change to Access
Level 2.
Courtesy of NationalSwitchgear.com
To Next Page
Loading...
