Overcurrent Elements
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Winding 2 Time-Overcurrent Timing Test
The instructor will apply the test values to the relay at three times the element pickup.
Step 1
Reset relay targets by pushing the
{TARGET RESET}
pushbutton located on the relay front panel.
Step 2
Clear the SER entries.
You can perform this task by using either the
SER C
serial port command or the
AC
SEL
ERATOR
QuickSet HMI.
Step 3
After the instructor applies the fault current, use the
TAR
n
serial port command (
n
= the Relay Word bit
for the element under test) or the
AC
SEL
ERATOR
QuickSet HMI to verify the overcurrent element pickup.
Step 4
Verify that the relay indicator for the Winding 2 phase time-overcurrent element 51P2T asserts at the
calculated test time.
Step 5
Calculate the error percentage using the following formula:
% error = (recorded – calculated)/calculated
Step 6
Ensure the error percentage is within ±5 percent for this timing test.
