ABB RELION REX640 - Timer; Blocking logic; 4.7.5.6 Application

Forward
opera�ng
area
Reverse
opera�ng
area
Non-
opera�ng
area
Z
2
Ng Seq impedance Fw
Ng Seq impedance Rv
Z
ero Value
Figure 579: Fault direction estimation on negative sequence impedance level
Timer
Once activated, the Timer activates the START output. The timer characteristic is
according to DT. When the operation timer has reached the value set by
Operate
delay time , the OPERATE output is activated if the operating conditions persists.
If a drop-off situation happens, that is, a fault suddenly disappears before the
operate delay is exceeded, the timer reset state is activated. If the reset timer
reaches the value set by Reset delay time , the operate timer resets and the START
output is deactivated. The timer calculates the start duration value START_DUR,
which indicates the percentage ratio of the start situation and the set operation
time. The value is available in the monitored data view.
Blocking logic
There are three operation modes in the blocking function. The operation modes are
controlled by the BLOCK input and the global setting in Configuration> System>
Blocking mode which selects the blocking mode. The BLOCK input can be controlled
by a binary input, a horizontal communication input or an internal signal of the relay
program. The influence of the BLOCK signal activation is preselected with the global
setting Blocking mode .
The Blocking mode setting has three blocking methods. In the "Freeze timer" mode,
the operation timer is frozen to the prevailing value, but the OPERATE output is not
deactivated when blocking is activated. In the "Block all" mode, the whole function is
blocked and the timers are reset. In the "Block OPERATE output" mode, the function
operates normally but the OPERATE output is not activated.
1MRS759142 F
Protection functions
REX640
Technical Manual
1041