Two Step Overvoltage Protection Ov2Ptov; Identification; Application - ABB Relion REC670 Applications Manual

Section 8
Voltage protection
CrvSatn
×
B
100
EQUATION1448 V1 EN-US
IntBlkSeln : This parameter can be set to Off , Block of trip , Block all . In case of a low voltage the
undervoltage function can be blocked. This function can be used to prevent function when the
protected object is switched off. If the parameter is set
is prevented.
IntBlkStValn : Voltage level under which the blocking is activated set in % of UBase . This setting
must be lower than the setting
that is, about 10%.
tBlkUVn : Time delay to block the undervoltage step n when the voltage level is below
IntBlkStValn , given in s. It is important that this delay is shorter than the operate time delay of
the undervoltage protection step.
8.2

Two step overvoltage protection OV2PTOV

8.2.1

Identification

Function description
Two step overvoltage protection
8.2.2

Application

Two step overvoltage protection OV2PTOV is applicable in all situations, where reliable
detection of high voltage is necessary. OV2PTOV is used for supervision and detection of
abnormal conditions, which, in combination with other protection functions, increase the
security of a complete protection system.
High overvoltage conditions are caused by abnormal situations in the power system. OV2PTOV
is applied to power system elements, such as generators, transformers, motors and power
lines in order to detect high voltage conditions. OV2PTOV is used in combination with low
current signals, to identify a transmission line, open in the remote end. In addition to that,
OV2PTOV is also used to initiate voltage correction measures, like insertion of shunt reactors,
to compensate for low load, and thereby decreasing the voltage. The function has a high
measuring accuracy and hysteresis setting to allow applications to control reactive load.
OV2PTOV is used to disconnect apparatuses, like electric motors, which will be damaged when
subject to service under high voltage conditions. It deals with high voltage conditions at
power system frequency, which can be caused by:
1. Different kinds of faults, where a too high voltage appears in a certain power system, like
metallic connection to a higher voltage level (broken conductor falling down to a crossing
178
- >
C 0
Un< . As switch of shall be detected the setting can be very low,
IEC 61850
identification
OV2PTOV
Block of trip or Block all unwanted trip
IEC 60617 ANSI/IEEE C37.2
identification device number
59
3U>
SYMBOL-C-2U-SMALLER-THAN V2 EN-US
1MRK 511 358-UEN A
(Equation 93)
IP14545-1 v3
M17002-1 v7
M13799-3 v8
Application manual