Schweitzer Engineering Laboratories SEL-351-5, Instruction Manual

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13.6
SEL-351-5, -6, -7 Relay Instruction Manual
Date Code 20070117
Testing and Troubleshooting
Testing Methods and Tools
➤
Apply low-level test signal V
AB
to pin VA.
➤
Apply low-level test signal –V
BC
(equivalent to V
CB
) to pin
VC.
➤
Do not apply any signal to pin VB.
Refer to Delta-Connected Voltages (Global Setting PTCONN = DELTA) on
page 2.13 for more information on the delta connection.
Test Methods
Test the pickup and dropout of relay elements using one of three methods:
➤
target command indication
➤
output contact closure
➤
sequential events recorder (SER)
The examples below show the settings necessary to route the phase time-
overcurrent element 51PT to the output contacts and the SER. The 51PT
element, like many in the SEL-351, is controlled by enable settings and/or
torque control SEL
OGIC®
control equations. To enable the 51PT element, set
the E51P enable setting and 51PTC torque control settings to the following:
E51P = 1 (via the SET command)
51PTC = 1 (set directly to logical 1, via the SET L command)
Testing Via Target Commands
Display the state of relay elements, inputs, and outputs using the front-panel
or serial port
TAR commands. Use this method to verify the pickup settings of
protection elements.
Testing With the Front-Panel TAR Command
Access the front-panel
TAR
command from the front-panel
{OTHER}
pushbutton
menu. To display the state of the 51PT element on the front-panel display,
press the
{OTHER} pushbutton, cursor to the
TAR
option, and press {SELECT} .
Press the {Up Arrow} pushbutton until
TAR 6
is displayed on the top row of the
LCD. The bottom row of the LCD displays all elements asserted in Relay
Word Row 6. The relay maps the state of the elements in Relay Word Row 6
on the bottom row of LEDs. The 51PT element state is reflected on the LED
labeled
RS . See Table 9.5 for the correspondence between the Relay Word
elements and the TAR command.
Testing With the Serial Port TAR Command
To view the 51PT element status from the serial port, issue the TAR 51PT
command. The relay will display the state of all elements in the Relay Word
row containing the 51PT element.
Review TAR command descriptions in Section 10: Serial Port
Communications and Commands and Section 11: Front-Panel Interface for
further details on displaying element status via the TAR commands.
Testing Via Output Contacts
You can set the relay to operate an output contact for testing a single element.
Use the
SET L command (SEL
OGIC
control equations) to set an output
contact (e.g., OUT101 – OUT107 for Model 0351 x 1) to the element under test. The
available elements are the Relay Word bits referenced in Table 9.5 .