Connect the injection current and voltage to terminals A and neutral.
2.
Set the injected polarizing voltage slightly larger than the set minimum polarizing
voltage (default 1% of Vn) and set the injection current to lag the voltage by an angle
equal to the set reference characteristic angle (
AngleRCA
), if the forward directional
function is selected.
If reverse directional function is selected, set the injection current to lag the
polarizing voltage by an angle equal to RCA+ 180°.
3.
Increase the injected current and note the value at which the studied step of the
function operates.
4.
Decrease the current slowly and note the reset value.
5.
If the test has been performed by injection of current in phase A, repeat the test,
injecting current into terminals B and C with a polarizing voltage connected to
terminals B, respectively C.
6.
Block lower set steps when testing higher set steps according to the instructions that
follow.
7.
Connect a trip output contact to a timer.
8.
Set the injected current to 200% of the operate level of the tested step, switch on the
current and check the time delay.
For inverse time curves, check the operate time at a current equal to 110% of the
operate current for
txMin
.
9.
Check that all trip and trip contacts operate according to the configuration (signal
matrixes)
10. Reverse the direction of the injected current and check that the step does not operate.
11. Check that the protection does not operate when the polarizing voltage is zero.
12. Repeat the above described tests for the higher set steps.
13. Finally, check that pickup and trip information is stored in the event menu.
6.3.6.2
Four step non-directional residual overcurrent protection
1.
Do as described in
"Four step directional residual overcurrent protection"
, but
without applying any polarizing voltage.
6.3.6.3
Completing the test
Continue to test another function or end the testing by setting the parameter
TestMode
to
Disabled
under
Main menu/Tests/IED test mode/TESTMODE:1
. If another function is
tested, then set the parameter
Blocked
to
No
under
Main menu/Tests/Function test
modes/Current/EF4PTOC(51N67N,4IN>)/EF4PTOC:X
for the function, or for each
individual function in a chain, to be tested next. Remember to set the parameter
Blocked
to
Yes
, for each individual function that has been tested.
Section 6
1MRK 505 293-UUS A
Testing functionality
52
Commissioning manual
