ABB REG650 Commissioning Manual page 86

Section 6
Testing functionality
78
1. Connect the test set for injection of three-phase currents to the appropriate
current terminals of the IED.
2. Go to Main menu/Settings/IED Settings/Current/NS2PTOC(46I2,2I2>)/
NS2PTOC:1/General and make sure that the function is enabled, that is
Operation is set to On.
3. Inject current into IEDs in such a way that negative sequence component is
created and then verify that negative sequence component of the injected
currents is calculated correctly by the function. See example below for 1 A rated
current transformer.
4. Inject pure negative sequence current, that is, phase currents with exactly same
magnitude, reversed sequence and exactly 120° phase displaced into the IED
with an initial value below negative sequence current start level. No output
signals should be activated.
Note: If it is difficult to obtain pure negative sequence current for the secondary
injection test, a current corresponding to the two phase short-circuit condition
can be used. A two phase short-circuit gives a negative sequence current of a
magnitude: magnitude = (1/√3) · fault current.
5. Increase the injected current and note the value at which the step 1 of the function
operates. Start signal ST1 must be activated when amplitude of the negative
sequence current lies slightly above the start level I2-1>. Corresponding trip
signals TR1 and TRIP is activated after the pre-set time delay has expired.
Note: Block or disable operation of step 2 when testing step 1 if the injected
current activates the step 2.
6. Decrease the current slowly and note the reset value.
7. Connect a trip output contact to a timer.
8. Set the current to 200 % of the start level of the step 1, switch on the current and
check the definite time delay for trip signals TR1 and TRIP. Once the measured
negative sequence current exceeds the set start level I2-1>, the settable definite
timer t1 starts to count and trip signals is released after the set time delay has
elapsed. The same test must be carried out to check the accuracy of definite time
delay for ALARM signal.
Note: The output ALARM is operated by START signal.
9. If inverse time is selected the trip signals TR1 and TRIP operates after a time
corresponding to the formula:
This means that if current jumps from 0 to 2 times start and negative sequence
capability value of generator K1 is set to 10 sec and current start level I2-1> is

1

2
 − > 
I 2 1

 
 

[ ] 100
=
t s

( )
2
Multiple of Start



1MRK 502 049-UEN A




⋅
K K




Commissioning manual