ABB RELION REF615R, Техническое руководство

Страница: 249 / 664

GUID-66143AD1-B4FB-4D99-86F4-BEBF74F80E3E-ANSI V1 EN
Figure 116: Functional module diagram
Level detector
The calculated negative-sequence voltage is compared to the set Pickup value setting. If
the value exceeds the set Pickup value , the level detector enables the timer.
Timer
Once activated, the timer activates the
PICKUP
output. The time characteristic is
according to DT. When the operation timer has reached the value set by Trip delay time ,
the
TRIP
output is activated if the overvoltage condition persists. If the negative-
sequence voltage normalizes before the module trips, the reset timer is activated. If the
reset timer reaches the value set by
Reset delay time , the operation timer resets and the
PICKUP
output is deactivated.
The timer calculates the pickup duration value PICKUP_DUR, which indicates the ratio
of the pickup situation and the set trip 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 protection relay's
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 timers" mode, the
operation timer is frozen to the prevailing value, but the
TRIP
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 TRIP output" mode, the function operates normally but the
TRIP
output is not activated.
1MRS240050-IB C
Section 4
Protection functions
REF615R 243
Technical Manual