Built-In Overvoltage Protection Steps - ABB Relion 650 Series Technical Manual

Section 6
Multipurpose protection
6.1.7.5
6.1.7.6
6.1.7.7
102
one. Reset of the start and trip signal can be instantaneous or time delay in
accordance with the setting.

Built-in overvoltage protection steps

Two overvoltage protection steps are available. They are absolutely identical and
therefore only one will be explained here.
Overvoltage step simply compares the magnitude of the measured voltage quantity
(see table 40) with the set pickup level. The overvoltage step will pickup if the
magnitude of the measured voltage quantity is bigger than this set level.
The start signal will start definite time delay or inverse (IDMT) time delay in
accordance with the end user setting. If the start signal has value one for longer
time than the set time delay, the overvoltage step will set its trip signal to one.
Reset of the start and trip signal can be instantaneous or time delay in accordance
with the end user setting.
Built-in undervoltage protection steps
Two undervoltage protection steps are available. They are absolutely identical and
therefore only one will be explained here.
Undervoltage step simply compares the magnitude of the measured voltage
quantity (see table 40) with the set pickup level. The undervoltage step will pickup
if the magnitude of the measured voltage quantity is smaller than this set level.
The start signal will start definite time delay or inverse (IDMT) time delay in
accordance with the end user setting. If the start signal has value one for longer
time than the set time delay, the undervoltage step will set its trip signal to one.
Reset of the start and trip signal can be instantaneous or time delay in accordance
with the end user setting.
Logic diagram
The simplified internal logics, for CVGAPC function are shown in the following
figures.
The following currents and voltages are inputs to the multipurpose protection
function. They must all be expressed in true power system (primary) Amperes and
kilovolts.
1. Instantaneous values (samples) of currents & voltages from one three-phase
current and one three-phase voltage input.
2. Fundamental frequency phasors from one three-phase current and one three-
phase voltage input calculated by the pre-processing modules.
3. Sequence currents & voltages from one three-phase current and one three-
phase voltage input calculated by the pre-processing modules.
1MRK 511 424-UEN B
M13751-234 v3
M13751-239 v3
M13085-3 v7
Bay control REC650 2.2 IEC
Technical manual