Arc Flash Protection Application - ABB REX640 Product Manual

REX640
Product version: 1
3I
3I
REX640
Base Functionality
Inst. ANSI IEC
4x AFD ARC
Incoming Feader
GUID-FCEB1FAB-ED80-4086-AABF-FA58F644F0A3 V1 EN
Figure 12.

Arc flash protection application

Figure 12 presents an installation-wide arc flash protection
scheme for a double busbar switchgear. REX640 protection
relays are equipped with arc flash sensor card. The card
supports a maximum of four pieces of either loop or lens
sensors or a combination thereof. By using suitable sensor
combinations for different bays, we can build up a selective arc
flash protection scheme for the complete switchgear. The
selective operation of the arc flash protection scheme limits the
power outage caused by the arc fault to the smallest possible
ABB
Loop sensor
Loop sensor
3I 3I
Loop sensor
REX640 REX640
Base Functionality Base Functionality
Inst. ANSI IEC Inst.
4x AFD ARC 4x
Outgoing Feader Bus coupler
REX640
Base Functionality
ANSI IEC Inst.
AFD ARC 4x AFD
Outgoing Feader
section of the switchgear. The arc flash protection operation is
not dependent on light detection only; it is also supervised by
arc fault current measurement. Since the arc flash protection
operation should be as fast as possible, the use of static power
outputs for tripping circuits is highly recommended. The
functional condition of the arc flash sensor is continuously
supervised and if a problem is detected, an alarm is triggered;
this applies to both loop and lens sensors.
1MRS759144 A
3I 3I
3I
REX640
Base Functionality
Inst. ANSI
ANSI IEC
4x AFD
ARC
Incoming Feader
IEC
ARC
15