Schweitzer Engineering Laboratories SEL-2701 - Page 73

5.5
Date Code 20020501 SEL-2701 Ethernet Processor Instruction Manual
SEL-400 Series Host
Operation
Control Points
The SEL-2701 and relay exchange binary control information via control
points. The relay sends control points CCOUT1–CCOUTn to the SEL-2701
for outgoing protocol data. Incoming message data appear in the relay as
incoming control points CCIN1–CCINn. The total number of CCOUT and
CCIN points represented by the n in the previous references varies in different
relay models.
The SEL-2701 automatically uses the CCOUT1–CCOUTn control points in
outgoing messages. For example, the SEL-2701 uses outgoing control points
to generate GOOSE messages. Use the relay output settings to set these bits
with SEL
OGIC control equations. Access these settings using the relay SET O
command. See your relay instruction manual for a full description of the
output logic settings.
Both input and output control points are Relay Word bits. You can use these
control points in any SEL
OGIC control equation in the relay including settings
for protection and automation free-form logic. You can view the control point
status using the relay TAR command.
Status Information
You can obtain status information on the SEL-2701 directly from the
SEL-2701 and through the relay. Connect to the SEL-2701 or relay and use
the STATUS command to view status messages and error codes. See
Section 6: Troubleshooting for more information on collecting status
information from the SEL-2701 and host.
SEL-2701 Alarm
The SEL-2701 alarm is automatically included in the SEL-400 series relay
SALARM bit. Conditions that activate an SEL-2701 alarm also activate the
SEL-400 series relay alarm light and output contact. For example, the
SEL-2701 sets the alarm bit if you are unsuccessful when changing access
levels with the ACC or 2AC command. The ACC and 2AC commands allow
you three attempts to enter the password. If you enter an incorrect password
on the third attempt, the SEL-2701 automatically sets the access level to 0 and
activates the alarm bit.
Testing
Use the SEL-400 series relay command TEST DB to test communication with
master devices by sending test values to the SEL-2701. The test values replace
measured values without disturbing relay protection functions. For example,
you can force the value of A-phase current in the database to a test value that
you can observe in the UCA2 MMXU model. See the relay instruction manual
for details of the TEST DB command.