Siemens SIPROTEC 7UT613 series Manual page 162

2 Functions
High-set Stages I>>
162
characteristic can be performed here. The definite time stages I>> and I> are available
in all cases.
If a second or third phase overcurrent protection is used, this must be configured ac-
cordingly in address 130 DMT/IDMT Phase2 and 132 DMT/IDMT Phase3.
Each protection function must be assigned to a side of the main protected object or
another 3-phase current measuring location. This can be carried out separately for
each protection function (section 2.1.4 under margin heading „Additional Three-phase
Protection Functions"). Consider also the assignment of the measured current inputs
of the device against the measuring locations (current transformer sets) of the power
plant (section 2.1.4 under margin heading „Assignment of 3-phase Measuring Loca-
tions").
Note
If the time overcurrent protection is assigned to a side of the main protected object,
the current values are set referred to the rated current of that side II/I
current values are set in amps.
At address 2001 PHASE O/C, phase overcurrent protection may be switched to ON or
OFF. The option Block relay allows to operate the protection but the trip output
relay is blocked.
Address 2008 MANUAL CLOSE determines which phase current stage is to be activat-
ed instantaneously with a detected manual close. Settings I>> instant. and I>
instant. can be set independently from the selected type characteristics;Ip
instant. is only available if one of the inverse time stages is configured. This setting
can only be made with DIGSI under Additional Settings.
If time overcurrent protection is applied on the feeding side of a trans-
former, select the higher stage I>>, which does not pick up by the inrush current or set
the manual close feature to Inactive.
In address 2002 InRushRest. Ph inrush restraint (restraint with 2nd harmonic) is
enabled or disabled for all phase current stages of time overcurrent protection (except
stage I>>). Set ON if one time overcurrent protection stage is to operate at the supply
side of a transformer. Otherwise, retain setting OFF. If you intend to set a very small
pickup value for any reason, consider that the inrush restraint function cannot operate
below 10 % nominal current (lower limit of harmonic filtering).
The I>> stage (address 2011 or 2212) combined with the I> stage or the Ip stage,
results in a two-stage characteristic. If one stage is not required, the pickup value has
to be set to ∞. Stage I>> always operates with a defined delay.
If time overcurrent protection is used on the supply side of a transformer, a series re-
actor, a motor or starpoint of a generator, this stage can also be used for current grad-
ing. Setting instructs the device to pick up on faults only inside the protected object but
not for traversing fault currents.
. In other cases,
NS
7UT613/63x Manual
C53000-G1176-C160-2