Overcurrent Feature With Voltage Restraint; Overcurrent Feature With Directionality - ABB RET670 Commissioning Manual

Section 11
Testing functionality by secondary injection
11.8.1.3
11.8.1.4
228

Overcurrent feature with voltage restraint

Procedure
1. Connect the test set for injection of three-phase currents and three-phase voltages to
the appropriate current and voltage terminals of the IED.
2. Inject current(s) and voltage(s) in a way that relevant measured (according to setting
parameter CurrentInput and VoltageInput) currents and voltages are created from
the test set.
Overall check in principal as above (non-directional overcurrent feature)
3. Trip value measurement
The relevant voltage restraining value (according to setting parameter
VoltageInput) has also to be injected from the test set and the influence on the trip
value has to be calculated when testing of the trip value is done.
4. Trip time measurement
Definite times may be tested as above (non-directional overcurrent feature). For
inverse time characteristics the PICKUP value (to which the overcurrent ratio has to
be calculated) is the actual pickup value as got with actual restraining from the
voltage restraining quantity.

Overcurrent feature with directionality

Please note that the directional characteristic can be set in two different ways either just
dependent on the angle between current and polarizing voltage (setting parameter
DirPrinc_OC1 or DirPrinc_OC2 set to or in a way that the trip value also is dependent on
the angle between current and polarizing voltage according to the I · cos(F) law (setting
parameter DirPrinc_OC1 or DirPrinc_OC2 set to I · cos(F). This has to be known if a
more detailed measurement of the directional characteristic is made, than the one
described below.
Procedure
1. Connect the test set for injection of three-phase currents and three-phase voltages to
the appropriate current and voltage terminals of the IED.
2. Inject current(s) and voltage(s) in a way that relevant measured (according to setting
parameter CurrentInput and VoltageInput) currents and voltages are created from
the test set.
3. Set the relevant measuring quantity current to lag or lead (lag for negative RCA
angle and lead for positive RCA angle) the relevant polarizing quantity voltage by
an angle equal to the set IED characteristic angle (rca-dir) when forward directional
feature is selected and the CTWYEpoint configuration parameter is set to ToObject.
If reverse directional feature is selected or CTWYEpoint configuration parameter is
set to FromObject, the angle between current and polarizing voltage shall be set
equal to rca-dir+180°.
1MRK 504 165-UUS -
Transformer protection RET670 2.2 ANSI
Commissioning manual