ABB RET670 Commissioning Manual page 171

1MRK 504 154-UUS B
VDepMode = Slope , the minimum measured phase-to-phase voltage is lower than
If
0,25*
than
•
•
•
Second section of the characteristic only:
If VDepMode = Slope , the minimum measured phase-to-phase voltage is between 0,25* VBase
and
•
•
•
Last section of the characteristic:
VDepMode = either Slope or Step , the minimum measured phase-to-phase voltage is higher
If
than
•
•
•
4. Inject the voltages that are related to the first part of the characteristic, and then slowly
increase the phase current IA from 0.0 A up to the value the function trips. The PICKUP and
STOC signals must be activated when the amplitude of the phase current IA is slightly above
0.25 A on the secondary side. The corresponding trip signals TROC and TRIP will be activated
after the pre-set time delay has expired.
5. Decrease the current IA slowly and note the reset value.
6. Repeat steps 4 and 5 applying voltages that are related to the second and the last section of
the characteristic; the function trips when IA is slightly higher than: 0.5 A in the second
section; 5A in the last section.
7. Connect the trip output contact to the input channel of the test set in order to stop the
injection and measure the trip time.
8. If definite time delay is used for the overcurrent step, set the setting
Time . Apply the voltages related to the last part of the characteristic and inject a current IA
200% higher than the set tripping level, and check the definite time delay for trip (the signals
TROC and TRIP of the protection function VRPVOC are active in trip condition).
9. If inverse time delay is used for the overcurrent step, the parameter setting
be properly set; we can refer, for example, to the setting
time characteristic is selected, the trip signals TROC and TRIP will trip after a time defined by
the equation:
t s [ ]
ANSIEQUATION2435 V1 EN-US
where:
t
I
Pickup_Curr Set trip value
Commissioning manual
VBase ; if VDepMode = Step , the minimum measured phase-to-phase voltage is lower
VHighLimit /100* VBase :
VA: Ampl = 10 / √3; Angle = 0°
VB: Ampl = 10 / √3; Angle = 240°
VC: Ampl = 100 / √3; Angle = 120°
VHighLimit /100* VBase :
VA: Ampl = 50 / √3; Angle = 0°
VB: Ampl = 50 / √3; Angle = 240°
VC: Ampl = 100 / √3; Angle = 120°
VHighLimit /100* VBase :
VA: Ampl = 105/ √3; Angle = 0°
VB: Ampl = 105/ √3; Angle = 240°
VC: Ampl = 105 / √3; Angle = 120°
13 5 . * k
=
I
 
1
 −

Pickup Curr _
 
Trip time in seconds
Measured value (for example, phase current)
Testing functionality by secondary injection
Characterist = ANSI Def.
Characterist shall
IEC Very inv. ; If the IEC Very inverse
Section 10
(Equation 94)
165