ABB RET670 Installation And Commissioning Manual page 142

Section 13
Verifying settings by secondary injection
136
1. Connect the test set for appropriate current injection to the appropriate IED
phases.
If there is any configuration logic that is used to enable or block any of the
four available overcurrent steps, make sure that the step under test is enabled,
for example end fault protection.
If 1 out of 3 currents for operation is chosen: Connect the injection current to
phases L1 and neutral.
If 2 out of 3 currents for operation is chosen: Connect the injection current
into phase L1 and out from phase L2.
If 3 out of 3 currents for operation is chosen: Connect the symmetrical three-
phase injection current into phases L1, L2 and L3.
2. Connect the test set for the appropriate three-phase voltage injection to the
IED phases L1, L2 and L3. The protection shall be fed with a symmetrical three-
phase voltage.
3. Set the injected polarizing voltage slightly larger than the set minimum
polarizing voltage (default is 5% of UBase) and set the injection current to lag
the appropriate voltage by an angle of about 80° if forward directional
function is selected.
If 1 out of 3 currents for operation is chosen: The voltage angle of phase L1 is
the reference.
If 2 out of 3 currents for operation is chosen: The voltage angle of phase L1 –
the voltage angle of L2 is the reference.
If 3 out of 3 currents for operation is chosen: The voltage angle of phase L1 is
the reference.
If reverse directional function is selected, set the injection current to lag the
polarizing voltage by an angle equal to 260° (equal to 80° + 180°).
4. Increase the injected current and note the operated value of the tested step of
the function.
5. Decrease the current slowly and note the reset value.
6. If the test has been performed by injection of current in phase L1, repeat the
test when injecting current into phases L2 and L3 with polarizing voltage
connected to phases L2 respectively L3 (1 out of 3 currents for operation).
7. If the test has been performed by injection of current in phases L1 – L2,
repeat the test when injecting current into phases L2 – L3 and L3 – L1 with
appropriate phase angle of injected currents.
8. Block higher set stages when testing lower set stages according to below.
9. Connect a trip output contact to a timer.
10. Set the injected current to 200% of the operate level of the tested stage,
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.
11. Check that all trip and start contacts operate according to the configuration
(signal matrixes)
12. Reverse the direction of the injected current and check that the protection
does not operate.
1MRK 504 088-UEN C
Installation and commissioning manual