ABB REB670 - Settings for each Step (X = 1, 2, 3 and 4)

ActUndrTimeSel: Describes the mode to activate the sensitive undertime function. The
function can be activated by Circuit breaker position (change) or Circuit breaker
command.
tUnderTime
: Time delay for operation of the sensitive undertime function. The setting
range is 0.000 - 60.000 s in step of 0.001 s. The default setting is 0.300 s
7.3.2.5 Settings for each step (x = 1, 2, 3 and 4)
M15282-9 v12
Operation: Sets the protection to Enabled or Disabled.
DirModeSelx: The directional mode of step x. Possible settings are Disabled/Non-
directional/Forward/Reverse.
Characteristx: Selection of time characteristic for step x. Definite time delay and
different types of inverse time characteristics are available.
Inverse time characteristic enables fast fault clearance of high current faults at the same
time as selectivity to other inverse time phase overcurrent protections can be assured.
This is mainly used in radial fed networks but can also be used in meshed networks. In
meshed networks, the settings must be based on network fault calculations.
To assure selectivity between different protections, in the radial network, there has to
be a minimum time difference Dt between the time delays of two protections. To
determine the shortest possible time difference, the operation time of protections,
breaker opening time and protection resetting time must be known. These time delays
can vary significantly between different protective equipment. The following time
delays can be estimated:
Protection trip time: 15-60 ms
Protection resetting time: 15-60 ms
Breaker opening time: 20-120 ms
The different characteristics are described in the technical reference manual.
tx: Definite time delay for step x. The definite time tx is added to the inverse time when
inverse time characteristic is selected. Note that the value set is the time between
activation of the start and the trip outputs.
Pickup"x": Operate residual current level for step x given in % of IB.
INx>Max and INx>Min should only be changed if remote setting of operation current
level, INx>, is used. The limits are used for decreasing the used range of the INx>
setting. If INx> is set outside INx>Max and INx>Min, the closest of the limits to INx>
is used by the function. If INx>Max is smaller than INx>Min, the limits are swapped.
Section 7 1MRK 505 370-UUS A
Current protection
202 Busbar protection REB670 2.2 ANSI
Application manual