Settings For Each Step (X = 1, 2, 3 And 4) - ABB REB670 Applications Manual

Section 7
Current protection
7.3.2.1
184
GlobalBaseSel: Selects the global base value group used by the function to define (IBase),
(VBase) and (SBase).
Operation: Sets the protection to Enabled or Disabled.

Settings for each step (x = 1, 2, 3 and 4)

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 have to be
a minimum time difference Dt between the time delays of two protections. The minimum
time difference can be determined for different cases. 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 operate time:
Protection resetting time:
Breaker opening time:
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 IBase.
kx: Time multiplier for the dependent (inverse) characteristic for step x.
IMinx: Minimum operate current for step x in % of IBase. Set IMinx below Pickupx for
every step to achieve ANSI reset characteristic according to standard. If IMinx is set above
for any step then signal will reset at current equals to zero.
INxMult: Multiplier for scaling of the current setting value. If a binary input signal
(MULTPUx) is activated the current operation level is increased by this setting constant.
15-60 ms
15-60 ms
20-120 ms
1MRK 505 337-UUS -
Application manual