Sel SEL-DTA2, Инструкция по эксплуатации

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3.7
Date Code 20020329
SEL-DTA2 Instruction Manual
Communications
Command Descriptions
NOTE:
After entering new
passwords, type PASSWORD <ENTER> to
inspect them. Make sure they are
what you intended and record the new
passwords. SEL-DTA2 passwords must
match passwords set for the relay.
Passwords can be any length up to six numbers, letters, or any other printable
characters except delimiters (space, comma, semicolon, colon, slash). It is
important that you establish strong password protection to safeguard against
unauthorized access. Strong passwords consist of six characters, with at least
one special character or digit and mixed case sensitivity, but do not form a
name, date, acronym, or word. Passwords formed in this manner are less
susceptible to password guessing and automated attacks. Examples of valid,
distinct strong passwords include:
Ot3579 A24.68 Ih2dcs 4u-Iwg Ic-4)=
WARNING:
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.
!
If you lose passwords and are unable to gain access to the SEL-DTA2, you can
temporarily disable password protection.
Step 1. Turn off the SEL-DTA2 and remove the cover.
Step 2. Disconnect the display cable from the display module and turn
the unit back on.
Step 3. The SEL-DTA2 will disable password protection, allowing you
to execute the PASSWORD command and display the current
passwords.
QUIT
(Access Level 1)
QUIT command execution returns control to Access Level 0 from Access
Level 1 or 2 and displays the instrument I.D., date, and time. Use this
command when you finish communicating with the SEL-DTA2 to prevent
unauthorized access. Note that control may return to Access Level 0
automatically after a settable interval of no activity (see TIME1 setting, SET
command).
SET (Access
Level 2 only)
The setting procedure requires you to answer prompting messages with new
data or press
<ENTER> to indicate no change. When you have entered all
data, the SEL-DTA2 displays the new settings and issues a prompt requesting
approval to enable them. After you approve new settings, the SEL-DTA2
triggers the output reset, clearing the contact outputs and any analog outputs
dedicated to fault location.
Error messages indicate when new entries are out of range or of the wrong
type.
An example SET command display appears at the end of this section; settable
parameters are defined as follows:
TIME1 controls the timeout interval of communications Port 1. This setting
range is from 0 to 30 minutes. A setting of 0 disables Port 1 timeout.
LOCK specifies the time after a fault during which analog and contact output
changes are suppressed for outputs dedicated to fault location. If, for example,
a fault was immediately followed by two reclose faults within three seconds,
only the first fault would affect the analog and contact outputs (using the
example LOCK setting of 300 cycles).
RESET specifies the length of time after a fault before analog and contact
outputs dedicated to fault location are automatically reset. The example
setting requires the SEL-DTA2 to wait for two minutes before resetting the
outputs. The character “0” specifies no automatic reset.
Settings MINW and MAXW specify the fault location window. Faults with
locations outside this window are ignored by the SEL-DTA2. Using the
example settings, a fault with a location of 75.34 miles would be captured,
stored, displayed, and presented at the contact and analog outputs. A reverse