10-32
Testing and Troubleshooting
Date Code 20020129
SEL-387E Instruction Manual
SLP1 = slope 1 setting
SLP2 = slope 2 setting
IRS1 = intersection where SLP2 begins
IRT = restraint quantity at which the calculation is carried out
For example:
Slope 1 = 25 percent
Slope 2 = 60 percent
PCT2 = 20 percent
IRS1 = 3, and choose IRT = 6
(
)
Ü
Ý
Û
Ì
Í
Ë
-
-
-
Ü
Ý
Û
Ì
Í
Ë
=
KDUPRQLF
= 15.75 percent
Note:
The second and fourth harmonics are combined to form the restraint
quantity.
Over-/Undervoltage Elements
Purpose: Verify the operation of over- and undervoltage elements.
Verify the operation of overvoltage elements.
Step 1.
Connect a source of variable three-phase voltage to the relay as shown in Figure
10.5.
Step 2.
Purpose: Verify the expected phase overvoltage pickup setting.
Method: Execute
the
SHOWSET
command via the relay front panel or serial port
and verify the setting (i.e.,
SHO 59P1P<ENTER>
).
Step 3.
Purpose: Display the appropriate Relay Word bit on the front-panel LEDs.
Method: Execute
the
TARGET
command (i.e.,
TAR F 59P1<ENTER>
). The
SEL-387E Relay now displays the state of the overvoltage elements on
the bottom row of front-panel LEDs.
Step 4.
Purpose: Apply balanced three-phase voltage below the setting and raise one phase
voltage until the appropriate LED illuminates.
Method: Apply balanced three-phase voltages as shown in Figure 10.5, adjusted to
a value below the
59P1P
setting. Raise one phase voltage until the
59P1
LED illuminates. The voltage should equal the
59P1P
setting
±2 V
and
±5% of setting. Repeat the test for the other two phases.