ABB Rellon 620 Series Technical Manual

1MAC309294-MB F Section 4
Protection functions
RER620 213
Technical Manual
4.3.5 Negative sequence overvoltage protection 47
4.3.5.1 Identification
4.3.5.2 Function block
Figure 97: Function block
4.3.5.3 Functionality
The negative-sequence overvoltage protection 47 is used to detect negative-sequence
overvoltage conditions. 47 is used for the protection of machines.
The function picks up when the negative-sequence voltage exceeds the set limit. 47
operates with the definite time (DT) characteristics.
The function contains a blocking functionality. It is possible to block function outputs, the
definite timer or the function itself, if desired.
4.3.5.4 Operation principle
The function can be enabled and disabled with the Operation setting. The corresponding
parameter values are Enable and Disable.
The operation of negative sequence overvoltage protection can be described by using a
module diagram. All the blocks in the diagram are explained in the next sections.
Figure 98: Functional module diagram. V
2
is used for representing negative phase
sequence voltage.
Level detector
The calculated negative sequence voltage is compared with the set Pickup value setting. If
the value exceeds the set Pickup value, the level detector enables the timer.
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Negative sequence overvoltage protection NSPTOV U2> 47
V
2
BLOCK
Level
detector
TRIP
PICKUP
Blocking
logic
t
Timer

ABB Rellon 620 Series Specifications

General

Brand	ABB
Model	Rellon 620 Series
Category	Controller
Language	English